WETFIX BE (CRALANE CAR 81)
WETFIX BE (CRALANE CAR 81)
synonyms: liquid, additive; LIQUID, ADDITIVE; LQUD, ADDTVE; ADTVE; ADDT; WETFX, BE, B,E, WET, FIX, FX, WETFXBE; WETFIX, BE; wetfixbe, wetfix, be; wet, fix, be; Cralane car 81; CRALANE, CAR, 81; CRLAN CAR 81; CRAL, CAR, 81; CRALAN CAR 81; cralanecar,81; Heat-Stable Adhesion Promoter; multipurpose adhesion agent for use in bitumen, road oils and cut-back binders; Bitumen binder; Asphalt Application; WETFIX BE; wetfix be; wetfxBE; WETFIX BE; WETFIXBE; DAMN HBG; DIAMINE HBG; diamine hbg; diamin hbg; sv, katk maddesi; SIVI, KATKI; LQUD, KATKI; ADTVE; addit; WETFX, BE, B, E, WET, DÜZELTME, FX, WETFXBE; WETFIX, BE; wetfixbe, wetfix, olmak; slak, düzeltmek; Cralane arabas 81; CRALAN, CAR, 81; CRLAN CAR 81; CRAL, CAR, 81; KRAL ARABASI 81; cralanecar, 81; Isya Kararl Yapma Arttrcs; bitüm, yol yalar ve kesme balayclarnda kullanm için çok amaçl yaptrma maddesi; Bitümlü balayc; Asfalt Uygulamas; WETFIX BE; slak düzeltme; wetfxBE; WETFIX BE; WETFIXBE; DAMN HBG; DIAMINE HBG; diamin hbg; diamin hbg; liquid, additive; LIQUID, ADDITIVE; LQUD, ADDTVE; ADTVE; ADDT; WETFX, BE, B,E, WET, FIX, FX, WETFXBE; WETFIX, BE; wetfixbe, wetfix, be; wet, fix, be; Cralane car 81; CRALANE, CAR, 81; CRLAN CAR 81; CRAL, CAR, 81; CRALAN CAR 81; cralanecar,81; Heat-Stable Adhesion Promoter; multipurpose adhesion agent for use in bitumen, road oils and cut-back binders; Bitumen binder; Asphalt Application; WETFIX BE; wetfix be; wetfxBE; WETFIX BE; WETFIXBE; DAMN HBG; DIAMINE HBG; diamine hbg; diamin hbg; sv, katk maddesi; SIVI, KATKI; LQUD, KATKI; ADTVE; addit; WETFX, BE, B, E, WET, DÜZELTME, FX, WETFXBE; WETFIX, BE; wetfixbe, wetfix, olmak; slak, düzeltmek; Cralane arabas 81; CRALAN, CAR, 81; CRLAN CAR 81; CRAL, CAR, 81; KRAL ARABASI 81; cralanecar, 81; Isya Kararl Yapma Arttrcs; bitüm, yol yalar ve kesme balayclarnda kullanm için çok amaçl yaptrma maddesi; Bitümlü balayc; Asfalt Uygulamas; WETFIX BE; slak düzeltme; wetfxBE; WETFIX BE; WETFIXBE; DAMN HBG; DIAMINE HBG; diamin hbg; diamin hbg; liquid, additive; LIQUID, ADDITIVE; LQUD, ADDTVE; ADTVE; ADDT; WETFX, BE, B,E, WET, FIX, FX, WETFXBE; WETFIX, BE; wetfixbe, wetfix, be; wet, fix, be; Cralane car 81; CRALANE, CAR, 81; CRLAN CAR 81; CRAL, CAR, 81; CRALAN CAR 81; cralanecar,81; Heat-Stable Adhesion Promoter; multipurpose adhesion agent for use in bitumen, road oils and cut-back binders; Bitumen binder; Asphalt Application; WETFIX BE; wetfix be; wetfxBE; WETFIX BE; WETFIXBE; DAMN HBG; DIAMINE HBG; diamine hbg; diamin hbg; sv, katk maddesi; SIVI, KATKI; LQUD, KATKI; ADTVE; addit; WETFX, BE, B, E, WET, DÜZELTME, FX, WETFXBE; WETFIX, BE; wetfixbe, wetfix, olmak; slak, düzeltmek; Cralane arabas 81; CRALAN, CAR, 81; CRLAN CAR 81; CRAL, CAR, 81; KRAL ARABASI 81; cralanecar, 81; Isya Kararl Yapma Arttrcs; bitüm, yol yalar ve kesme balayclarnda kullanm için çok amaçl yaptrma maddesi; Bitümlü balayc; Asfalt Uygulamas; WETFIX BE; slak düzeltme; wetfxBE; WETFIX BE; WETFIXBE; DAMN HBG; DIAMINE HBG; diamin hbg; diamin hbg;
WETFIX BE, iyi s stabilitesinin gerekli olduu scak karm asfalt için özel olarak tasarlanm bir sv katk maddesidir. WETFIX BE, kayda deer etkinlik kayb olmadan, 170 ° C’ye kadar olan scaklklarda 5 güne kadar scak bitümde depolanabilir. Wetfix BE, Akzo Nobel Surface Chemistry tarafndan scak ve lk karm için bir yapma arttrc ve souk ve scak karm için üretilir.Yumuak ziftlere veya kesiklere dayanr. Köpüklü asfalt souk karm için aderans arttrc ve kaplama yardmcsdr. Çok yönlü Yumuak bitüm karmlar da dahil olmak üzere çok çeitli uygulamalar için uygun yapma arttrc. WETFIX BE dozaj kullanlan bitüm ve agrega tipi. Balaycya normal olarak% 0.2 ila% 0.5 arasnda ilave edilir. Wetfix BE bitüm, yol ya ve azaltma balayclar olarak kullanm için çok amaçl bir yapkan maddenin olduu sl stabilite, likidite ve düük uçuculua avantajlaryla. Wetfix BE’nin stabilitesi scaktr bitüm asit deeri ve bitümün scaklna Ancak baldr. Bitümlü balayclarn özelliklerine ilikin gereklilikler Avrupa standartlarnda belirlenmitir. Bitümenin fiziko-kimyasal davran, kolloidal yapsna (esas olarak ham kaynana ve ilenmesine bal olan doymu yalar, aromatikler ve reçineler tarafndan oluturulan yal bir matrikse dalm asfaltenler) baldr. Bitüm özellikleri, grup kompozisyonu, temel analiz, ancak daha sklkla geleneksel veya fonksiyonel testler ile deerlendirilir. Yol kullanmlar için bitüm, fiziksel özelliklerine göre deerlendirilir. Bitüm ve asfaltlarn kalitatif özelliklerinin gelitirilmesi amacyla, katk maddeleri, örn. elastikiyetini arttrmak, s stabilitesini arttrmak, agregasyona yapmay arttrmak, viskoziteyi azaltmak, yalanmaya kar direnci arttrmak, agrega yüzeyinden balayc drenaj önlemek, vb. Sunumun amac, katk maddelerinin özellikleri üzerindeki etkisini deerlendirmek ve karlatrmaktr. bitüm balayclar. Kâtta, bitüm özelliklerinin, penetrasyonun, yumuama noktasnn ve bitüm 35/50, 50/70 ve polimer modifiye bitümlü PmB 45 / 80-75’in dinamik viskozitesinin sonuçlar incelenmitir. agregaya yapmay iyiletirmek ve ilenebilirlii gelitirmek için seçilen katk maddelerinin (Sasobit, Licomont BS100, Wetfix BE ve CWM) uygulanmas. Mallarn ölçümleri ilgili Avrupa standartlarna göre gerçekletirilmitir. Laboratuar testleri, kaldrm dereceli bitüm 50/70 ve 35/50 ‘nin 13 ila 45 ° C arasndaki yumuama noktasn önemli ölçüde arttrdn gösterdi. Çeitli katk maddelerinin bitüm yumuama noktas üzerindeki etkisi farkldr. Penetrasyon, bitüm tipine ve kullanlan katk maddesine göre deiir. Katk maddeleri Sasobit ve Licomont BS100 ile modifiye bitüm PmB 45 / 80-75’in penetrasyon deerleri, 16 0.1mm bitüm sertliinin artmasn ve geçite bir kayma olduunu göstermektedir. Penetrasyon indeksinde scaklk duyarll parametresi olarak hesaplanrken penetrasyon ve yumuama noktalarndaki deiiklikler önemli ölçüde gösterilmitir. Katk maddeleri, bitümün viskozitesini çounlukla deitirilmi bitüm ile daha düük deerlere deitirmitir. Katk maddesi 35/50 orannda kartrlm Wetfix BE karm durumunda viskozite artar. Katk maddesi, orijinal bitümlü balayclarn özelliklerini deitirir ve bu da asfalt karmlarnn ve asfalt tabakalarnn özelliklerini etkileyebilir.
Faydalar ve Özellikleri
-Versatil ürün: Wetfix BE hem aktif hem pasif yapma salar ve çok çeitli asfalt karmlarnda ve sprey uygulamalarnda kullanlr.
-Value for Money: Wetfix BE, düük dozaj ve düük ilem maliyetleri ile konsantre bir üründür.
-stik Stabilite: Scak bitümde depolandktan sonra performans korunur.
-Düük volatilite: Ürün, solvent içermez ve scak karm scaklklarnda düük volatiliteye sahiptir.
-Kullanm Kolayl: Ürün dier konsantre antistriplere göre daha düük viskoziteye sahiptir.
Paketleme Bilgileri
Wetfix BE, dökme yüklerde, 190kg (419 lb) net arla sahip tamburda veya 900kg’lk tek yönlü kutuda (IBC’ler) temin edilir. WETFIX BE, çelik bidonlarda (190 kg’lk net) ve ara yük konteynerlerinde (900) teslim edilir. kg net). Ürün, orijinal kapal konteynerinde en az iki yl stabildir.
Daha fazla bilgi
Daha fazla bilgi, teknik servis ve numuneler için lütfen en yakn Akzo Nobel Sat ofisimize veya temsilci / distribütörümüze bavurun. WETFIX BE, iyi s stabilitesinin ihtiyaç duyulduu scak karm asfalt için özel olarak üretilmi sv bir katkdr. (BSK) Bitümlü Scak Karm ve Sathi Kaplamalarda Konforlu bir ekilde kullanlr.
Neden WETFX BE?
-180 0C lik slardaki scak bitümde özelliklerini kaybetmeden minimum 5 güne kadar tutulabilme özelliine sahiptir.
-Az kokulu ve rahatsz edici deildir.
-Düük oranda kullanlr.(binde bir ile binde iki orannda)
-UV nlarna kar korunakldr.
-Su hasarn minimize eder.
-Çatlaklar minimize eder.
-Tekerlek oturma izini minimize eder.
-Mükemmel derecede Aderans artrr.
-Bazalt, kalker, granit, andazit, grandiorit tipteki talarla mükemmel uyum salar.
-Amerika dahil Dünyann 80 ülkesinde kullanlmaktadr.
-20 C ile 0 C’de uygulanabilme özelliinden dolay souk havalarda da bitüme kolaylkla ilave edilir. (Kara Yollar Teknik artnamesi K.T.. Ksm 411’e uygundur.)
-Üretimleri (ÇM) ndirek Çekme Testinden geçirildikten sonra piyasaya arz edilir.
WETFIX BE is a liquid additive, specially designed for hot-mixed asphalt where good heat stability is required. WETFIX BE may be stored in hot bitumen for up to 5 days at temperatures up to 170ºC without significant loss of activity. Wetfix BE is produced by Akzo Nobel Surface Chemistry an adhesion promoter for hot and warm mix, and for cold and warm mix based on soft bitumens or cut-backs. It’s an adhesion promoter and coating aid for foamed asphalt cold mix. Versatile adhesion promoter suitable for a wide range of applications including soft bitumen mixes.The dosage of WETFIX BE depends on the type of bitumen and aggregate used. Normally between 0.2 and 0.5% is added to the binder. Wetfix BE is a multipurpose adhesion agent for use in bitumen, road oils and cutback binders with the advantages of heat stability, liquidity and low volatility. The stability of Wetfix BE in hot bitumen depends however on the acid value and the temperature of the bitumen. Requirements for properties of bituminous binders are determined in the European standards. The physico-chemical behaviour of bitumen depends on its colloidal structure (asphaltenes dispersed into an oily matrix constituted by saturates, aromatics and resins) that depends primarily on its crude source and processing. Bitumen properties are evaluated by group composition, elementary analysis, but more often conventional or functional tests. Bitumen for road uses is assessed according to the physical characteristics. For the purpose of improving the qualitative properties of bitumen and asphalts the additives are applied e.g. to increase elasticity, improving the heat stability, improving adhesion to aggregate, to decrease viscosity, increasing the resistance to aging, to prevent binder drainage from the aggregate surface, etc. The objective of presented paper is to assess and compare effect of additives on properties of bitumen binders. In paper, the results of bitumen properties, penetration, softening point, and dynamic viscosity of two paving grade bitumen 35/50, 50/70 and polymer modified bitumen PmB 45/80-75 are analyzed and also the changes of these properties by the application of selected additives (Sasobit, Licomont BS100, Wetfix BE and CWM) to improve adhesion to aggregate and improve workability. Measurements of properties have been performed according to the relevant European standards. The laboratory tests showed significantly increasing the softening point of paving grade bitumen 50/70 and 35/50 by 13 to 45°C. The effect of various additives on bitumen softening point is different. Penetration varies according to type of bitumen and type of used additive. The penetration values of modified bitumen PmB 45/80-75 with additives Sasobit and Licomont BS100 show increase of bitumen stiffness of 16 0.1mm and a shift in the gradation. The changes in penetration and in softening point significantly shown when calculating on Penetration index as a parameter of temperature susceptibility. The additives changed the viscosity of bitumen to lower values mostly with modified bitumen. In case of the additive Wetfix BE mix in 35/50caused the viscosity increase. The additive changes the properties of original bituminous binders, and that can affect the properties of asphalt mixtures and asphalt layers.
Benefits and Features
-Versatile product: Wetfix BE provides both active and passive adhesion and finds use in a wide range of asphalt mixtures and spray applications.
-Value for Money: Wetfix BE is a concentrated product with consequent low dosage and low treatment costs.
-Heat Stability: The performance is maintained after storage in hot bitumen.
-Low Volatility: The product does not contain solvents and has low volatility at hot mix temperatures.
-Easy to Use: The product has lower viscosity than other concentrated antistrips.
Packaging Information
Wetfix BE is available in bulk shipments, in tight head drums of 190kg (419lb) net weight, or in one-way totes (IBCs) of 900kg.WETFIX BE is delivered in steel drums (190 kg net) and intermediate bulk containers (900 kg net). The product is stable for a minimum of two years in its original closed container.
Further Information
For further information, technical service and samples, please contact our nearest Akzo Nobel Sales office or agent/distributor.
Why WETFIX BE?
-It has the ability to hold up to 5 days without losing its properties in hot bitum at -180 ° C.
-It is odorous and uncomfortable.
-It is used in a low proportion (two in one and one in)
-It is sheltered against UV rays.
-Minimizes water damage.
-Minimize cracks.
-The seat minimizes the sitting trace.
-It’s excellent.
-Basalt, limestone, granite, andazite, grandiorite perfect match with the type of stone.
-It is used in 80 countries of the world including America. Because of its ability to be applied at -20 ° C to 0 ° C, the bitumen is easily added even in cold weather (Technical Specifications of Land Roads are suitable for KT.. Section 411.)
-They are introduced to the market after they are passed through the Indirect Tensile Test (ICM).
All information concerning this product and/or all suggestions for handling and use contained herein are offered in good faith and are believed to be reliable. Surface Chemistry AB, however, makes no warranty as to the accuracy and/or sufficiency of such information and/or suggestions, as to the product’s merchantability or fitness for any particular purpose, or that any suggested use will not infringe any patent. Nothing contained herein shall be construed as granting or extending any license under any patent. Buyer must determine for himself, by preliminary tests or otherwise, the suitability of this product for his purposes. This information contained herein supersedes all previously issued bulletins on the subject matter covered.Akzo Nobel Surface Chemistry AB, S-444 85 Stenungsund, Swedenhttp://www.akzonobel.com/scVersion: 1.2Issued: 21 Sep 2009
Heat-Stable Adhesion Promoter for Bituminous Binders
WETFIX® BE
Heat-Stable Adhesion Promoter for Bituminous
Binders
Application WETFIX BE is a liquid additive, specially designed for hot-mixed asphalt where good heat stability is required.
WETFIX BE may be stored in hot bitumen for up to 5 days at temperatures up to 170ºC without significant loss of activity.
Dosage The dosage of WETFIX BE depends on the type of bitumen and aggregate used. Normally between 0.2 and 0.5% is added to the binder.
Physical Properties
Appearance at 20ºC Brown, viscous liquid
Density at 20ºC, kg/m³ 980
Pour point, ºC <0
Flash point, ºC >100
Viscosity at 20ºC, cP 3000
Viscosity at 50ºC, cP 400
Note: Above values are average and subject to minor variations.
Specification Property Value Unit Method of Analysis
Total Amine Number 160-185 mg HCl/g 234
Acid Value <10 mg KOH/g 225
Package and
Storage
WETFIX BE is delivered in steel drums (190 kg net) and intermediate bulk containers (900 kg net). The product is stable for a minimum of two years in its original closed container.
Handling and
Safety
A Safety Data Sheet is available.
Wetfix BE
Specifications
Total amine number160-185 mg HCl/g90 KL 0050Acid value<10 mg KOH/g90 KL 0051
ParameterLimitsMethodTypical Data
Flash point218°CPour point< 0°CViscosity, 20°C800 cPAppearance, 20°Cbrown, viscous liquidDensity, 20°C980 kg/m³
Chemical and Physical dataTypical values
WETFIX® is a registered trademark in many countries.
Storage & Handling
Wetfix BE is delivered in steel drums (190 kg net) and intermediate bulk containers (900 kg net). The product is stable for a minimum of two years in its original closed container.
Typical data are based on our own measurements or derived from the literature. They do not constitute part of the delivery specifications.
Asphalt Applications7WETFIX® 312
Application Liquid antistrip for hot-mix asphalt pavements.
Advantages ·Heat Stability: Wetfix 312 meets the heat stability test requirements of state highway testing laboratories.
·Concentrated Liquid: Wetfix 312 is a concentrated product with consequent low dosage level.
Typical Dosage 0.25-1.0% by weight of asphalt is recommended, which should be determined in laboratory mix design tests.
Wetfix 312 is preferably added to the asphalt at the hot-mix plant by means of a specially designed injection system.
Alternatively, the product can be incorporated into the asphalt by mechanical agitation, pump circulation of the storage tank, or by injection into the asphalt loading line followed by recirculation through
the truck bypass system until properly mixed.
Physical
Properties
Appearance at 25°C Dark brown liquid
Pour point, °C <0 (<32°F)
Flash point, °C >200 (> 392°F )
10 20 30 40 °C
50 68 86 104 °F
Viscosity, mPa.s (cP) 2250 1500 800 370
Density, g/cc 0.98 0.97 0.96 0.96
Density, lbs./gal 8.15 8.06 8.02 7.96
See reverse for additional data
Storage and
Handling
Wetfix 312 may be stored in carbon steel tanks. Bulk storage should be maintained at 10-40°C (50-105°F). Avoid heating above 65°C (150°F).
Wetfix 312 contains amines and may cause severe irritation or burns to skin and eyes. Protective gloves and safety goggles must be used when handling this product. For further information, consult the Material Safety Data Sheet.
Packaging
Information
Wetfix 312 is available in bulk shipments or in 55-gallon tight-head drums of 400 lbs. (181 kg) net weight.
Wetfix 312
All information concerning this product and/or suggestions for handling and use contained herein are offered in good faith and are believed to be reliable. , however, makes no warranty as to the accuracy and/or sufficiency of such information and/or
suggestions, as to the product’s merchantability or fitness for any particular purpose, or that any suggested use will not infringe any patent. Nothing contained herein shall be construed as granting or extending any license under any patent. Buyer must determine for himself, by
preliminary tests or otherwise, the suitability of this product for his purposes. The information contained herein supersedes all previously issued bulletins on the subject matter covered.
Notes For regulatory reasons this product is not available in Canada.
Viscosity vs. Temperature
0
500
1000
1500
2000
2500
50 60 70 80 90 100 110 120
Temperature (°F)
Viscosity (cp)
Density vs. Temperature
7.96
7.98
8.00
8.02
8.04
8.06
8.08
8.10
8.12
8.14
40 50 60 70 80 90 100
Temperature (°F)
WETFIX BE
Heat-Stable Adhesion Promoter for Bituminous Binders
Specification Limits Method
Acid value 90 KL 0051
Total amine number 160-185 mg HCl/g 90 KL 0050
Typical data
Chemical and physical data Typical values
Appearance, 20°C brown, viscous liquid
Density, 20°C 980 kg/m³
Flash point 218°C
Pour point <0°C
Viscosity, 20°C 800 cP
The specifications and properties listed above are intended for products manufactured in Europe.
Application
Wetfix BE is a multipurpose adhesion agent for use in bitumen, road oils and cut-back binders with the advantages of heat stability, liquidity and low volatility. The stability of Wetfix BE in hot bitumen depends however on the acid value and the temperature of the bitumen.
Dosage
For active adhesion, e.g. surface dressing 0.5-1.0 %
For passive adhesion, e.g. hot mix 0.2-0.5 %
Packing and Storage
Wetfix BE is delivered in steel drums (190 kg net) and intermediate bulk containers (900 kg net). The product is stable for a minimum of two years in its original closed container.
Handling and Safety
A Safety Data Sheet is available.
Further Information
For further information, technical service and samples
1
Asphalt Applications Andrew Tham
Market & product portfolio
New Roads
Aggregates
Asphalt
Prime Coat
Emulsion
Anti
Stripping
Tack Coat
Emulsion
Maintenance
Asphalt
layer
Tack Coat
MS/ Slurry
Seal
2
Emulsions
Redicote emulsifiers
Viscosity Modifier
Hot Mix
Wetfix Adhesion Promoters
Warm Mix
Rediset warm-mix additives
and compaction Aids
Asphalt Applications
3
Asphalt Applications
WETFIX® series of Products,
e.g. WETFIX® BE
Advantages of using WETFIX® BE:
– Safety
– Wider aggregate selection
– Prolongs lifetime of pavement
4
Asphalt Applications
Passive Adhesion Loss
5
Philippines Field Trial (2014)
Asphalt Applications
With 0.30% WETFIX® BE
(Left Lane) Without WETFIX® BE
(Right Lane)
Newly paved in Jan-2014:
6
Philippines Field Trial (2014)
Asphalt Applications
With 0.30% WETFIX® BE
(Left Lane)
Without WETFIX® BE
(Right Lane)
8 months later in
Sep-2014:
7
Surface Chemistry | Personal Care 8
Asphalt Applications
Active Adhesion Demonstration
Surface Chemistry | Personal Care 9
Asphalt Applications
Passive Adhesion
Static
Immersion Test
Surface Chemistry | Personal Care 10
Asphalt Applications
Static
Immersion Test
11
Asphalt Applications
Chemical Structure of WETFIX® BE
Bitumen
Amine
Group
Si
OH
Aggregate
12
Asphalt Applications
N
H3 +
O –
13
Asphalt Applications
Application of WETFIX® BE in
Malaysia
14
Asphalt Applications
Malaysia recognizes the need for Anti-Stripping agents.
Any substitute must be equivalent to Wetfix N422
15
Asphalt Applications
Condition Before Trial (5-July-2006)
Asphalt Applications
Surface Chemistry | Personal Care 17
Asphalt Applications
The Culprits?
– Heavy Trucks
– Rains
These factors, including others, make the roads very
vulnerable to Water Damage, and hence Stripping.
Newly Paved – Without WETFIX® BE (5-Jul-2006)
Malaysia Field Trial (2006)
Asphalt Applications
3 months later – Without WETFIX® BE (28-Oct-2006)
Malaysia Field Trial (2006)
Asphalt Applications
3 months later – With 0.30% WETFIX® BE (28-Oct-2006)
Malaysia Field Trial (2006)
Asphalt Applications
4 months 6 months 11 months
Without WETFIX® BE
Asphalt Applications
Malaysia Field Trial (2006)
4 months 6 months 11 months
With 0.30% WETFIX® BE
Malaysia Field Trial (2006)
Asphalt Applications
23
Asphalt Applications
Application of WETFIX® BE in
Indonesia
24
Asphalt Applications
Indonesia recognizes the need for Anti-Stripping agents.
Nowadays, in some projects especially around the Jakarta regions, it is a MUST to use Anti-Stripping Agents.
WETFIX® BE was the first Anti-Stripping agent to be approved and adopted by the country.
Document from Department of Public Works, Indonesia,
stating that all Anti-Stripping Agents must first be approved by the government Surface Chemistry | Personal Care 25
Asphalt Applications
Application of WETFIX® BE in
Vietnam
26
Asphalt Applications
and EDSTACHEM have been working closely with the relevant Vietnam authorities such as Institute of Transport Science and Technology Road Laboratory (ITST) on the implementation of WETFIX® BE since 2008 .
In a report released by ITST in 2008, the conclusion is as follows:
27
Vietnam Field Trial (2014)
Asphalt Applications
28
Vietnam Field Trial (2014)
Asphalt Applications
29
Asphalt Applications
1. Europe
– Sweden, Denmark, Norway – In Hot Mix specification
– Other European countries – common practices
2. USA
– Common practices in Hotmix, Thin Overlays etc
3. Australia/New Zealand
– Common practices in Chip Seal application
Other Case References
5. Other Countries
– Japan – in PMA, & in Porous Asphalt
– South Korea – in PMA, & in SMA
Surface Chemistry | Personal Care 30
Asphalt Applications
Surface Chemistry | Personal Care 31
Asphalt Applications
Cost of adding Wetfix®BE
Dosage of Wetfix®BE = 0.30% (by weight of Bitumen in Hotmix)
Assuming Bitumen % = 5.0% of Total Hotmix
In 1 ton of Hotmix = 150gm of Wetfix®BE
Cost of Hotmix = 4000 peso/ton
Cost of Wetfix®BE = 260 peso/kg
= 39 peso/150gm
% Cost of adding Wetfix®BE = (39/4000) x 100%
= ~1%
32
Asphalt Applications
How to add Wetfix®BE into Hotmix Plants
33
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“The world is evolving quickly and open innovation is helping Nouryon evolve right along with it. Through Imagine Chemistry we have formed several partnerships with startups whose exciting technologies are already starting to deliver value to our business.”
The purpose of asphalt binder as a significant binder in road constructions is to permanently bind aggregates of different compositions and grain sizes. The asphalt binder itself does not have suitable adhesiveness, so after a period of time, bare grains can appear. This results in a gradual separation of the grains from an asphalt layer and the presence of potholes in a pavement. Adhesion promoters or adhesive agents are important and proven promoters in practice. They are substances mainly based on the fatty acids of polyamides which should increase the reliability of the asphalt’s binder adhesion to the aggregates, thus increasing the lifetime period of the asphalt mixture as well as its resistance to mechanical strain. The amount of a promoter or agent added to the asphalt mixture is negligible and constitutes about 0.3% of the asphalt’s binder weight. Nevertheless, even this quantity significantly increases the adhesive qualities of an asphalt binder. The article was created in cooperatation with the Slovak University of Technology, in Bratislava, Slovakia, and focuses on proving the new AD2 adhesive additive and comparing it with the Addibit and Wetfix BE promoters used on aggregates from the Skutec – Litická and Bystrec quarries.
1 INTRODUCTION
Bitumen binder is a significant building material used both in road constructions and for other building purposes. The first references to the use of this material date back to ancient history. Increases in its use started at the beginning of the twentieth century with the rise of the petrochemical industry. Today, it is a commonly used material without which most road communications cannot be done. In the Czech Republic, 97% of the road communications contain asphalt surface wearing course. The asphalt layers of pavements comprise the upper construction of a non-solid pavement, which is directly exposed to the horizontal and tangential strain effects of vehicles. These effects are then shifted to other layers of the road construction. The top surface dressing (the abrasive/surface course) layer is directly exposed to atmospheric and climatic influences. The pavement surface dressing should therefore be impermeable, even, and have adequate anti-slip qualities throughout its lifetime so that safe, fast and comfortable ride is ensured. In order to meet these requirements, it is not only necessary to provide a suitable construction material (Stehlik at. al., 2015),
(Komacka at. al., 2014), (Wu at. al, 2015), but also to maintain the construction technology; otherwise, various defects such as an adhesion failure among the individual asphalt layers (Hamzah at. al., 2014)
or unsuitable surface properties on the abrasion layers may occur.
2 ADHESION OF ASPHALT BINDERS
When a solid substance contacts another solid, liquid, or gas substance, there is an attractive interaction between the particles at the and adhesion of all the components of the asphalt mixture. The adhesion between the aggregates and asphalt binder belongs among the important factors that influence the durability of asphalt layers. The interaction between the individual components of an asphalt mixture is dependent on the factors, see Fig. 1.
There are two types of adhesion of asphalt mixtures: active and passive. Active adhesion between an asphalt binder and an aggregate occurs when the binder is able to move water from the wet surface of the aggregate. Passive adhesion is caused by external forces, e.g., increased pore pressure, and can be described as resistance to water penetrating into a system while using asphalt mixtures (Georgy,1961).
In order to describe the bonding processes between an asphalt binder and aggregate, it is necessary to work on an adhesion theory (Nösler, 2000), (Masad at. al., 2004), which can be described by theoretical models (Volker at. al., 2009). For the most frequently used models, see Tab 1.
Tab. 1 Adhesion models between asphalt binders and aggregates
considered
Theory Interaction
Weak Boundary Layer theory layering
Mechanical theory interlock
Electrostatic theory potential
Chemical theory covalent and ionic bonds
Thermodynamic theory surface energy
3 FAILURE MODELS
The most frequently seen and common examples of adhesion
models that explain adhesion failures include pore pressure, displacement (see Fig. 2), infiltration, and boundary layer damage models (Volker at. al., 2009). These models rarely exist in isolation in practice; in most cases a combination of models occurs. Being affected by water is the one thing that these models have in common, because water is the main cause of adhesion failure (Hefer at. al., 2005), since water is a bipolar liquid. The double pole has a positive and negative charge, and the chemical bonds among the atoms make an angle of approximately 105°C. Water molecules are slightly attracted by the hydrophilic surface of the mineral (aggregate), so a saturation of the surface charges takes place. This results in a gradual displacement of a non-polar asphalt binder from the surface of the aggregates. Further minor factors include the transport loads, temperature conditions, and quality of the binder and aggregate. A marginal factor is also the thickness of the binder layer on the aggregates. In an experimental study, Mondal et al (Mondal at. al., 2012) carried out tensile tests on the interface of the aggregates and asphalt binder in order to determine the effect of the thickness of the asphalt binder on the way the damage occurred. The thickness of the asphalt film between the two polished aggregate surfaces ranged from 0.11 mm to 0.64 mm. A traction load was applied at 1 mm/min, and tests were carried out at 23°C. It was determined that the thickness of the asphalt binder does affect the adhesion and damages the bond between the aggregates and asphalt binder. With any increase in the thickness of the asphalt layer, the probability of the failure of the binder increases too.
4 ADHESION PROMOTERS
Adhesion promoters are chemicals that affect the interface between an organic polymer and an inorganic substrate and increase the adhesion between the two materials (Ebnesajjad, 2011). By changing the surface tension and reducing the viscosity, the asphalt binder F covers the surface of the aggregate better, which results in creating a strong bond (chemical bond) between the asphalt binder and aggregates, see Fig. 3.
It has been proved that silane-based adhesive additives promote the adhesion between organic and inorganic materials; furthermore, they extend their lifetime period in wet conditions (Cui at. al., 2014).
The effectiveness of these promoters is attributed to the fact that they act as a chemical bridge, where one part of the molecule is attached to an aggregate and the other part is bound to the asphalt binder (Packham, 2005). There are also amine-based adhesion promoters, which consist of long hydrocarbon chains and amine functional groups.
Hydrocarbon groups react with the asphalt binder and the aggregate reacts with the amine group, thereby increasing the aggregate wettability within the asphalt binder.
5 EXPERIMENT
The adhesion between aggregates and an asphalt binder cannot
be quantified. Adhesive bonds can be assessed according to adhesion
failure studies by various methods, such as chemical, mechanical,
thermodynamic or electrostatic testing.
As mentioned above, the greatest effect on an asphalt binder-aggregate system is most probably water (a stripping effect). Therefore, the sensitivity or resistance of moisture to a loss of adhesion is considered to be a suitable and indirect indicator of the ability of asphalt binder to adhere to aggregates (Volker at. al., 2009).
• Testing methods for dealing with sensitivity to moisture can be divided into two categories: Tests that are carried out on coated aggregate particles, such as rotating bottle, boiling water immersion, and immersion tests.
• Tests performed on a test body, i.e., with a compacted asphalt mixture such as the Kantabro, indirect tensile stress test (ITS), or abrasion tests.
For the purpose of this article, the methodology used for determining the adhesion of asphalt binders to aggregates is in accordance with CSN 73 6161: 2000. The determination of the adhesion of asphalt binders to aggregates, test parameters, see Tab. 2.
The adhesion of asphalt binder to aggregates is assessed according to CSN 73 6161 in the following way:
• excellent: if more than 75% of the grains of the test specimen have the characteristics of the connection of the asphalt binder film with the aggregate “A”; for the rest of the grains, the characteristics must not be less than “B” (the percentage of the coated area greater than approximately 97%);
• good: if more than 75% of the grains of the test specimen have the characteristics of the connection of the asphalt binder film with the aggregate “B” (or better); for the rest of the grains, the characteristics must not be less than “C” (the percentage of the coated area greater than approximately 90%);
pass: if more than 75% of the grains of the test specimen have
the characteristics of the connection of the asphalt binder film with the aggregate “C” (or better); for the rest of the grains the characteristics must not be less than “D” (the percentage of the coated area greater than approximately 80%);
• not pass: If less than 75% of the grains have the characteristics “C”. In order to study the adhesive qualities of a new additive, the following input materials were used. There are three new promoters listed in Tab. 4, including their descriptions. Furthermore, the 50/70 road asphalt binder and polymer modified asphalt binder PmB 45/80- 55, A1 aggregate, and A2 aggregate were used.
5.1.1 A1 Aggregate – 8/11
This aggregate mainly consists of amphibolic-biotic granodiorite. Granodiorite belongs among deep acid igneous rocks with a
SiO2
content higher than 65%. There are plagioclases predominant over feldspar potassium. The jointing of these rocks is cuboidal or heavy-bedded. The bulk weight ranges from 2600 – 2800 kg/m3 ; the Mohs hardness is 6 – 7; absorption is between 0.5 – 2.0%; and the compression strength is 120 – 240 MPa. Amphibole belongs among dark minerals; it forms columnar and needle-like crystals. They are perfectly fissible and parallel to the longitudinal axis of posts. The
cleavage areas are approximately 60°and 120°. Biotite (dark mica) has a hardness of 2.5 – 3 and a density of 3 – 3.1 g/cm3 . It is a blackish-brown or black scaly mineral of an uneven shape with a perfect cleavability.
5.1.2 A2 Aggregate – 8/16
This aggregate predominantly consists of regionally metamorphosed clay shale, i.e., paragneiss. It ranks among metamorphic
rocks formed by the regional conversion of sedimentary rocks. The
main macroscopic minerals are quartz, feldspar, mica, and sometimes
sillimanite. Subsidiary macroscopic mineral components are graphite, cordierite, and garnet. The bulk weight varies between 2650 and
2750 kg/m3
; the Mohs hardness is 6 – 7; the absorption is in the range
of 0.1 – 1.2%; and the compressive strength of this rock is 120 – -250
MPa.
The test specimens were prepared from the above-mentioned input materials, see Tab. 5.
6 ASSESSMENT OF THE EXPERIMENT
When using the AD2, Addibit, or Wetfix BE admixtures, the adhesion of all the specimens was achieved with an assessment of “good”. The asphalt mixtures that include these promoters will be able to be used according to CSN EN 13108-1 in the underlay, base,and surface courses in all classes of the traffic loads. Specimens without adhesive promoters with the modified PMB 45/80-55 asphalt binder were assessed as suitable and may be used according to CSN EN 13108-1 in the wear and bedding layers of
pavements with III, IV, VI and CH traffic loads. Specimens without adhesive promoters with the 50/70 road asphalt binder were assessed as unsatisfactory. This means that aggregates without promoters are not suitable for use in the construction layers of the pavements due to particular acidic rocks, which generally do not permit good adhesion, see Tab.6.
7 CONCLUSION
Based on the assessment of the results of the adhesion of the asphalt binder to the aggregates, it can be concluded that the new AD2 adhesive additive favourably affects the asphalt binder’s adhesion.
When used, it can be expected to have a beneficial effect on the durability (lifetime period) of a pavement construction, thus reducing life cycle costs (lower maintenance costs). Other findings that resulted
from carrying out the experiment include:
• Moisture has adverse effects on the adhesion of asphalt mixtures. The choice of a hydrophobic aggregate or the use of chemical promoters in a binder can help minimize this particular degradation.
• Adhesion within an asphalt binder aggregate system is a result of a combination of thermodynamic, mechanical and Effects of surfactants and adhesion promoters on the bitumenminerals interfacial bond during breaking of bitumen emulsions.
ABSTRACT
Cold mix asphalt (CMA) emulsion technology has been the subject of research for many decades due to its proven environmental and economic benefits. However, issues relating to its mechanical performance still need to be investigated in order to understand the breaking mechanisms of bitumen emulsions and the surface chemistry involved. Bitumen emulsions
are designed to break in a controlled manner to achieve the required level of performance for producing good quality cold asphalt mixtures. In this work, experiments on the coalescence of two bitumen droplets were carried out on a selected grade of Nynas bitumen. In an emulsion environment, the cohesion between bitumen droplets as well as their adhesion to a mineral
surface was investigated. The cohesion and adhesion properties were analyzed by varying selected surfactant types and adhesion promoters in the water phase. The research showed that the presence of emulsifiers (with concentrations above the critical micelle concentration) in the water phase inhibits the adhesion of bitumen droplets to the mineral surface. However, a
very small addition (0.02%) of adhesion promoter reverses the situation completely, and adhesion is dominant rather than cohesion. Moreover, the kinetics of the coalescence process is strongly controlled by the water phase temperature.
KEYWORDS: Cold Mix Asphalt; Bitumen Emulsions; Breaking and Coalescence; Cohesion; Adhesion; Surfactants; Minerals.
1. Introduction
Cold mix asphalt (CMA) emulsion technology has been the subject of research for many decades due to its proven environmental and economic benefits. CMA is usually produced by mixing bitumen emulsions (bitumen/water) or foamed bitumen (bitumen/air/water) with unheated minerals/aggregates at ambient temperatures. Due to its lower emissions and energy
consumption, the demand for bitumen emulsion is growing in the market [1-3]. Bitumen emulsions are produced by mixing hot bitumen and a water phase containing emulsifying agents using a very high shear force to disperse the bitumen into small droplets [4-6]. Bitumen emulsions are versatile, being used for road construction and maintenance. They are
also used in spray applications such as surface dressing or chip seal, fog seal, tack and prime coat, slurry or micro surfacing and cold mix paving, which is potentially the largest application area for bitumen emulsions [7].
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The mechanisms for bitumen emulsion stability are governed by intermolecular forces (a result of a balance of repulsive and attractive forces). The correct formulation of bitumen emulsions requires skills and basic knowledge about surface chemistry and physics to understand the intermolecular force balance that will guarantee better performance.
Developing a suitable emulsion formulation requires the selection of the right type of emulsifier and additives, suitable for the intended aggregate type, bitumen type and expected climate conditions. Surface active agents (generally referred to as surfactants or emulsifiers) are essential ingredients in the formulation of any dispersal system. An emulsifier acts as a
surface active agent that concentrates at the interphase region between two immiscible liquids such as oil and water [8].They are amphipathic molecules consisting of two parts, a polar head which is hydrophilic and a long carbon chain which is nonpolar lipophilic. This carbon chain can be a straight or branched hydrocarbon chain containing approximately 8 – 18 carbon
atoms, which are attached to a polar or ionic part (hydrophilic). The hydrophilic part can be non-ionic, ionic, or zwitterionic (amphoteric), accompanied by counter ions in the last two cases. The hydrocarbon chain interacts weakly with the water molecules in an aqueous environment, whereas the polar or ionic head group interacts strongly with water molecules
through dipole or ion-dipole interactions [9].
Emulsions have been classified in several ways, for example based on particle size (micro or macro emulsions), size distribution (mono/poly-dispersed), and concentrations (dilute, semidilute or concentrated) as well as according to surfactant molecule (anionic, cationic or nonionic). Bitumen emulsion lies in the macro emulsion category with a typical droplet size range
of 1 – 20 µm, and can be stabilized using anionic, cationic, or in some special cases non-ionic emulsifiers. Anionic emulsifiers used for bitumen emulsification are usually fatty acids, alkyl sulfates or sulfonates, which ionize in aqueous solutions to provide negatively charged organic ions that generate surface activity. The use of anionic emulsifiers started in the late
1920s and, after three decades of development, cationic emulsifiers have changed the bitumen emulsion market drastically and become the most widely used; they are currently very common in road construction applications. Cationic emulsifiers ionize in aqueous solution and provide organic ions with positive charges that are responsible for surface activity. They
are usually fatty amines and their derivatives (primary, secondary, tertiary, quaternary and many others). It is firmly believed by the road pavement industry that the amine-based additives improve adhesion, workability and also function as anti-stripping agents [10-12]. Non-ionic emulsifiers are different from the other two types. These surfactant molecules do
not ionize in aqueous solution but part of their molecule has a high affinity for water. On an industrial scale, they represent the main category of surfactant produced throughout the world, but their use in bitumen emulsion applications is limited. The most typical examples and molecular structures of the abovementioned surfactants are shown in Fig. 1.
Anionic Type
(Sulfates, Sulfonates,
Carboxylic Acid)
Cationic Type
(Amines and derivatives)
Non-ionic Type
(Ethoxylated Fatty Acids or
Alcohols, Nonyl Phenol
Ethoxylate)
Fig. 1: Types of emulsifier used for bitumen emulsions [13].
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Furthermore, amphoteric surface active agents ionize in aqueous solution to provide organic ions that are either positively charged at acidic pH with cationic polarity, or negatively charged at a basic pH with anionic polarity. Due to environmental concerns and economic reasons, the demand for this class of surfactant is growing the most rapidly of all of them [14].
In our previous work [15], we calculated the bond of adhesion in dry and wet conditions by measuring the surface free energies (SFEs) of both bitumen and minerals. In that work, the SFEs of bitumen with/without adhesion promoters were evaluated in two different ways. In the first method, adhesion agents were added directly to the hot bitumen, whereas in the
second method, these additives were added first to the water phase and then bitumen samples were stored in that water phase for approximately two days. The SFE results for bitumen with adhesion promoters revealed that the surface polarity of the bitumen samples was dramatically enhanced when stored in the water phase containing emulsifier and adhesion
agents. Due to the enhanced polar component of SFE, bond of adhesion calculations showed that there were improvements in the bond strength even in the wet conditions. However, we did not investigate actual contact between the bitumen and the mineral surface in the presence of water containing those additives. So we developed a new test procedure to investigate
bitumen droplet coalescence and their adhesion on a mineral surface. This paper aims to bridge the gap between the fundamental adhesion theory of asphalt and practical emulsionaggregate systems.
First, in the following section, the mechanisms of these processes are addressed in more detail.
1.1. Breaking and Coalescence Processes
Apart from the storage and transport stability requirements, the central property of bitumen emulsion is its ability to break or rupture in contact with minerals/aggregates. There are several breaking mechanisms which have been proposed in the literature, but the setting process of bitumen emulsions is a complex process which is still not fully understood [16].
The most important breaking mechanism is the absorption of emulsifiers on the surface of the stone, depleting the water phase of emulsifiers and causing the bitumen emulsion to break. However, other mechanisms have also been discussed in the literature, such as the porous and reactive surfaces of aggregates extracting the water from bitumen emulsions and leading to
breakage. Heteroflocculation and coagulation must take place within the desired time and at the right location. In the heteroflocculation process, bitumen droplets form clusters around the solid mineral particles before coalescence on the solid surface. In the coagulation stage, bitumen droplets coalesce on the stone surface, the water phase separates out and a layer of
bitumen coats the aggregate surface. Coalescence is the last stage in the breaking process of bitumen emulsions in which droplets merge into bigger ones. As illustrated in Fig. 2a, during coalescence, pairs or groups of droplets approach each other with negligible initial velocities, ouch and form tiny contact bridges due to Van der Waals interactions. The bridge contact
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length, rb, quickly expands under the influence of interfacial stress, finally resulting in complete fusion of small droplets into increasingly larger ones.
Fig. 2. Schematic illustrations of (a) the coalescence process in a breaking bitumen emulsion, and (b) bitumen coatings of aggregates resulting from good adhesion (left) and poor adhesion (right).
In coalescence, a film of bituminous binder develops that adheres to the aggregate, then sets and hardens (“cures”), thereby determining the mechanical strength of the cold asphalt mixture. Good adhesion can be achieved if the aggregate is completely wetted by the bitumen, but adhesion will be poor if premature coalescence occurs away from the surface or water is
still present at the interface, as illustrated in Fig. 2b. 1.2. Purpose of the study The primary goal of this research work was to improve the basic understanding of the breaking and coalescence processes in bitumen emulsions. A clear understanding of these processes and mechanisms is essential for improving formulations and procedures for use in
practical engineering projects.
The objectives of this paper are:
i) To visualize and characterize the coalescence of bitumen droplets and their adhesion to the mineral surface in an emulsion environment, using a custom-designed test.
ii) To analyze the effects of different surfactants and adhesion promoters on the coalescence and adhesion of bitumen drops on a mineral surface.
iii) To compare the adhesive properties of the mineral-bitumen interface measured in an emulsion environment with predictions based on the surface free energies of individual components.
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This work could be significant because the breaking and coalescence mechanisms in bitumen emulsions have not yet been fully understood. In this experimental study, we have tried to address the practical issues related to the coating of a stone surface by bitumen in the presence of water. We believe that this work will contribute to the filling of the research gap between
the fundamental adhesion theory of asphalt and practical emulsion-aggregate systems. The following sections of the paper describe a methodology, the experiment itself and the results. Then the research work is summarized, based on the experimental results, and conclusions are drawn.
2. Methodology
In this work, we have improved our previously used “bitumen droplet coalescence test set-up” [17], in order to visualize and characterize the coalescence of bitumen droplets and their adhesion to a mineral surface in an emulsion environment. The details of the test set-up and experimental design of the bitumen droplet relaxation test have been described in the previous
study. The test set-up consists of a camera and a light source as shown in Fig. 3a. There is a rectangular glass container with optically transparent walls placed in the middle, which is horizontally aligned and in the focus of a light source and a camera at two ends. Two metallic L-shaped probes with flexible vertical position settings are placed parallel to the glass
container. At the bottom where the glass container is placed, there is a Peltier heating panel which is connected to a water bath. There are additional humidity and temperature sensors attached to the climate chamber which is placed over a glass container and metallic probes. A polished mineral sample (see Fig. 3) was placed at the bottom of a glass container that was
filled with the water phase soap solution (with/without additives). The composition of the aqueous phase was similar to that usually prepared for manufacturing bitumen emulsions, and contains selective additives e.g. emulsifiers, salt and acid or base for pH adjustment. Bitumen droplets of 1 – 2 mm diameter were attached to the L-shaped probes and placed in a water
phase for pre-conditioning. There was no compression force applied while bringing the two droplets into contact; however, the two droplets were positioned close enough that they touched each other. A similar approach was used to study the coalescence of two droplets on a mineral surface where three point contacts were required, for instance, c1) contact between
two droplets, c2) first droplet with mineral surface, and c3) second droplet with mineral surface.
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Fig. 3. a) Experimental set-up for studying the coalescence of bitumen droplets, and b) bitumen droplets formed on a silicone mold.
Bitumen samples were heated in an oven to form a flowing liquid (160 to 180 o C, depending on bitumen grade) then droplets of various diameters were formed on the surface of a siliconepad (which provides a non-stick surface for bitumen) using a syringe and needles of appropriate sizes (Fig. 3b). After this, the mold and bitumen droplets were placed in a freezer
at -20 o
C for 2 – 3 hours to stabilize their shapes. After retaining a certain stiffness and the droplet shape, bitumen droplets were removed from the silicone pad with the help of small tweezers and attached to the L-shaped hooks to pre-condition them in water before starting the coalescence experiments. The coalescence experiments were carried out in the water
phase soap solutions when droplets reached the selected temperatures.
Relaxation of bitumen droplets can be defined as a three step process as shown in Fig. 4. The first step is usually called pre-relaxation, where bitumen droplets are placed in a water phase for some time to retain their circular shape. This step is also called the pre-conditioning step. In the second step, actual relaxation or coalescence of bitumen droplets starts where two
bitumen droplets merge into a single one. In the last step, the relaxed droplet is retained in a water phase to note any change in its shape. If the droplet does not relax further in the post relaxation process, then the experiment is stopped and the time of relaxation is noted which is the last step of relaxation.
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Fig. 4. Different stages in the relaxation process of bitumen droplets in water phase. The process of droplets coalescing when brought together was filmed with a video camera. To follow the contraction kinetics, images recorded at regular time intervals were analyzed using standard image processing software (Image J). The dimensions of fusing two bitumen drops
in the horizontal and vertical axial directions at time t were measured. Then coalescence times were determined from the images and used to assess the effects, on the process, of variables such as binder grades, bitumen droplet sizes, test temperatures, types of emulsifiers in the water phase (soap solution), additives (salts at various concentrations and adhesion
promoters), soap solution pH and other organic solvents.
As can be seen in Fig.4 and Fig.5, the shape relaxation process causes a gradual decrease in the axial length L(t), being a line joining the droplets’ centers. The contraction process was determined using the anisotropy factor p(t) which is defined as: p(t) = H(t)/L(t), where H(t) is the length of the contact bridge between two drops and perpendicular to the axial length L(t).
In the case of two drops with different sizes, the initial anisotropy ratios po will not be the same. We determined the normalized anisotropy where the initial radii of the two drops were denoted R and ßR with ß ? 1. The normalized anisotropy can be calculated as {1-p(t)}/{1-p0} [18]. For complete relaxation, two droplets must merge into a unique spherical droplet;
however, in this case, a complete fusion of two bitumen droplets was observed for a H/L ratio
of 0.8.
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Fig. 5. Diagram representing the start and the end points of the shape relaxation process.
3. Experimental design and investigated materials
In asphalt mixtures, the bitumen-aggregate adhesion has always been an issue when moisture is present. Specifically, in CMA, water could be the most dominant factor affecting the bond of adhesion between bitumen and aggregates as water molecules are always in competition with the bitumen molecules to displace each other from the aggregate surface. This, of course,
can be linked to the activity of the stone surface in terms of bonding with bitumen in the presence of water. Also, in the breaking behavior of bitumen-in-water emulsions, an important factor to understand is the water push out and wetting of the stone surface by bitumen [15]. For these reasons, an experiment was developed based on the flow chart of
experimental design factors as shown in Fig.6.
In this work, an emulsion grade of unaged and unmodified straight run Nynas bitumen with penetration grade 70/100 was used for the droplet relaxation experiment, at two differenttemperatures of water phase with selective additives. The water phase soap solutions were prepared using cationic, anionic and non-ionic surfactants with selected concentrations. The
cohesion between bitumen drops, as well as their adhesion to the mineral surface (granite), were analyzed with varying selected surfactant types and adhesion promoters in the water phase soap solution.
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Fig. 6. Experimental design factors and levels.
As previously found [19], several parameters influence this bond of adhesion e.g. roughness and porosity of aggregates, surface wettability and chemical composition at the interface. Most of the aggregates are very sensitive to moisture due to their surface porosity and chemical composition, especially those containing alkali metals (sodium, potassium). In this
paper, we have used non-porous granite which is acidic by nature. A typical granite contains quartz (SiO2), feldspar (KAlSi3O8, CaAl2Si2O8) and mica {KAl3Si3O10 (OH)2, K(Mg,Fe)3AlSi3O10(OH)2} [20]. Acidic and basic rocks are classified as hydrophilic and hydrophobic, respectively. The acidic or basic nature of rocks can be classified based on their
silica (SiO2) or calcite (CaCO3) content, respectively. Igneous rocks have been divided into four types based on overall silica content e.g. acidic (63 – 100%), basic (45 – 52%), ultrabasic (0 – 45%) and intermediate (52 – 63%). According to [21], the worldwide average of the chemical composition of granite, by weight percentage, is 72.04% SiO2, 14.42% Al2O3,
4.12% K2O, 3.69% Na2O, 1.82% CaO, 1.68% FeO, 1.22% Fe2O3, 0.71% MgO, 0.30% TiO2, 0.12% P2O5 and 0.05% MnO. The overall silica content in other aggregates are as follows: marble (0 – 25%), limestone (0 – 50%), dolomite (35 – 55%), basalt (40 – 50%), diorite (50 – 65%), sandstone (60 – 100%) and quartzite (85 – 100%) [22]. Hence, the chemistry of the
aggregate affects the degree of water sensitivity of the bitumen-aggregate bond and, in particular, the overall silica content in the minerals/aggregates.
In this study, granite was cut into a rectangular shape using a granite and marble saw blade. Then, the surface texture was made very smooth by polishing with silicon carbide (SiC) sandpaper (from coarse to fine mesh) without using any additional polish. All samples were washed with distilled water and dried in an oven at 110 o
C overnight.
A general chemistry of selected cationic and amphoteric (both cationic and anionic) surfactants from AkzoNobel Sweden is shown in Fig. 7. The four types of cationic emulsifiers
e.g. R-tallow diamine, R-tallow diamine ethoxylate, R-tallow amido-amine, and R-tallow Khan, Redelius, Kringos
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quaternary amine were used in this study. Additionally, one non-ionic emulsifier Redicote E47 NPF (nonyl phenol free), which is basically an R-tallow ethoxylate alcohol, and two anionic (amphoteric types) emulsifiers were selected for this study. Amphoteric types of surfactants can be used for both cationic (at pH = 2.3) and anionic (at pH=11) emulsifiers e.g.
Ampholak 7TX (tallow-ampho-poly-carboxy-glycinate) and Ampholak XCE (amine-based amphoteric of the glycinate type) etc.
Fig. 7. Chemical structures of selected emulsifiers [3, 13-14].
Along with the above surfactants, different adhesion promoters were also selected to investigate their effect on the coagulation of bitumen on a mineral substrate in the presence of water. These additives were Diamine OLBS (for active adhesion), WetFix BE (for passive adhesion) and WetFix N (for active and passive adhesion) from AkzoNobel Sweden.
Anhydrous CaCl2 from Sigma-Aldrich with reagent plus grade was also used in this study. Hydrochloric acid (HCl) and sodium hydroxide (NaOH) were used to control the pH of the soap solution.
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4. Results and discussion
In the first experiments using the droplet relaxation method, the coalescence or cohesion of two bitumen droplets was investigated with various surfactants in the water phase.
4.1. Coalescence or cohesion of bitumen droplets The bitumen droplet coalescence or cohesion test consists of two steps. First, coalescence of the two droplets occurs when the protective barrier or electric double layer is penetrated.
Then, there is shape relaxation of these two droplets when they merge into one. In this work, the relaxation test was carried out on only one grade of Nynas bitumen (pen. 70/100) at 40 and 50 o C. Since the viscosity of bitumen is very high at lower temperatures, the shape relaxation takes a very long time. For that reason, an intermediate temperature range was
selected to carry out the bitumen droplet coalescence test in an emulsion environment. Moreover, the relaxation kinetics of bitumen droplets were investigated in a water phase containing four cationic [(A) R-tallow diamine, (B) R-tallow diamine ethoxylate, (C) R-tallow amido-amine, and (D) R-tallow quaternary amine], one non-ionic [(E) R-tallow ethoxylated
alcohol], and two anionic (amphoteric) [(F) amine-based amphoteric of the glycinate type, and (G) R-tallow-ampho-poly-carboxy-glycinate] emulsifiers.
Fig. 8. Coalescence of bitumen droplets of indicated grade in water + emulsifier + with/without salt + hydrochloric acid (to pH=2.0) at 50 o C.
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The results of the droplet coalescence test in a water phase with selected compositions containing emulsifiers and salt are shown in Fig. 8. The relaxation time increases by adding emulsifiers as well as salt to the water phase. Similarly, a higher concentration of emulsifier slows down the coalescence process. A summary of experimental results illustrating droplet
coalescence without a mineral surface is given in Table 1. Table 1. Experimental results for bitumen (Pen.70/100) droplet coalescence in a water phase containing selective additives (e.g. emulsifiers, salt). Water Phase Composition Coalescence or Relaxation Time [mins]
At 50 o
C At 40 o
C
Water 11 45
0.2% A + HCl [pH 2.3] 30 180
0.2% A + HCl [pH 2.3] + 0.1M CaCl2 65 205
0.5% A + HCl [pH 2.3] + 0.1M CaCl2 153 250
0.2% B + HCl [pH 2.3] 16 100
0.2% B + HCl [pH 2.3] + 0.1M CaCl2 26 120
0.5% B + HCl [pH 2.3] + 0.1M CaCl2 40 185
1.0% B + HCl [pH 2.3] + 0.1M CaCl2 60 220
0.2% C + HCl [pH 2.3] 22 120
0.2% C + HCl [pH 2.3] + 0.1M CaCl2 90 210
0.2% D + HCl [pH 2.3] 15 150
0.2% D + HCl [pH 2.3] + 0.1M CaCl2 20 170
0.2% D + [pH 7.0] No Coalescence observed
0.2% D + [pH 7.0] + 0.1M CaCl (Relaxation kinetics are extremely slow) 2
Four sets of amine-based cationic emulsifiers (A to D) were tested with selected concentrations of each surfactant. It can be seen that activity of emulsifier D depends on pH. In most of the cases, for cationic rapid and medium setting emulsions, the pH was set between 2 to 3. The coalescence time for these emulsifiers can be compared at pH = 2.3, where
emulsifiers B and D exhibit almost the same activity, although less than emulsifiers C and A, respectively. However, for cationic slow setting bitumen emulsion applications, emulsifier D is used at neutral pH. Moreover, the coalescence test confirmed, as shown in Fig. 9, that bitumen droplets do not coalesce and that the relaxation kinetics are extremely slow in the
case of emulsifier D at neutral pH.
13
Fig. 9. Coalescence of bitumen droplets of indicated grade in water + emulsifier + with/without salt + ( pH=7.0) at 50 o
C.
The presence of surfactants or surface active molecules at the interface also changes the surface tension, and their variation in concentration gives rise to surface tension gradients. Moreover, the contraction or expansion of the interface may also affect concentrations of surfactants, which leads to variations in surface tension. In the early stages of coalescence,
during neck opening, droplet interfaces contract and if emulsifiers are present then such interface shrinkage will increase their concentration, thereby reducing surface tension. However, if surfactant concentrations are already high, above the critical micelle concentration (CMC), further increases (or small variations in surface area) will have very
small effects on the surface tension.
The water phases shown in Fig. 10 consist of soap solutions with emulsifiers A – D (Table 1) as well as some additional emulsifiers (E – G) and selected adhesion promoters such as diamine OLBS, WetFix N and WetFix BE. Table 2 shows the concentrations of selected emulsifiers in the water phase at a given pH.
Table 2. The concentrations of selected emulsifiers in the water phase at a given pH. The surface tensions of the water phases containing additives were measured using the Wilhelmy plate method [23] at ambient temperature. It can be seen in Fig. 10 that the surface tensions of the water phases changed with different functionality of the surfactant molecules
as well as salt addition.
Fig. 10. Surface tensions of selected aqueous phase compositions measured at ambient temperature using the Wilhelmy Plate method.
The coalescence of bitumen droplets as a function of the interfacial tensions (IFTs) of the water phases is plotted in Fig. 11, as measured using the Wilhelmy Plate technique. The study shows a weak correlation between the kinetics of bitumen droplet coalescence and the IFTs. Moreover, adding adhesion promoters to the water phase containing emulsifiers reduced IFTs
in all cases. For instance, in the case of a water phase containing surfactant A (R-tallow diamine), adding diamine OLBS resulted in a greater decrease in IFT than adding WetFix N and WetFix BE. However, in the case of surfactant B (R-tallow diamine ethoxylate), adding diamine OLBS and WetFix BE reduced the IFT at the same level. In contrast, adding WetFix
N yielded a very small decrease in IFT. This small reduction in IFTs of water phases due to addition of adhesion promoters may prolong the coalescence process. However, the surface activity of these soap solutions showed a little effect on the coalescence process.Khan, Redelius, Kringos
15
Fig. 11. Correlation diagram of the bitumen droplet relaxation time as a function of IFT of the aqueous phases containing selected emulsifiers types, and with and without adhesion
promoters.
4.2.Cohesion and adhesion of bitumen droplets
The cohesion and adhesion of bitumen droplets were investigated together. Fig. 12 shows bitumen droplet relaxation in pure water without any additives, where coalescence of two bitumen droplets occurred away from the mineral surface (Fig. 12a) and flush on the surface (Fig. 12b). At the end of the experiments shown in Figs. 12 – 18, the vertical positions of both
L-shaped hooks were moved upwards to detach the bitumen droplets from the stone surface in order to observe the adhesion. The results show that the relaxation times of two bitumen droplets are the same in both cases. Moreover, bitumen makes a good adhesion bond with the mineral surface in pure water but the coating is not uniform under the neck region of the two
bitumen droplets (see Fig. 12b at t = 53 mins).
Khan, Redelius, Kringos
16
Fig. 12. Bitumen (Pen.70/100) droplet coalescence at 50 o
C, a) in a water phase away from
stone surface and b) in a water phase on the granite surface.
Fig. 13. Bitumen (Pen.70/100) droplet coalescence on the granite surface at 50 o C, a) in a water phase containing emulsifier(R-Tallow Ethoxylated Diamine) at pH=2.3, without salt and b) with 0.1M CaCl2.
In the next step, bitumen droplets were tested for coalescence in a water phase containing 0.2% R-tallow ethoxylated diamine at pH=2.3, with and without salt (see Fig. 13a-b). The relaxation time of bitumen droplets in this environment exactly corresponded to the results given in Table 1. However, it can be seen that the presence of emulsifier rendered the mineral
surface non-stick for bitumen droplets. Adding very small amounts of adhesion promoters (0.02%) to the water phase containing R-tallow ethoxylated diamine reversed this completely. As shown in Fig. 14 a-c, all three adhesive agents e.g. diamine OLBS (Fig.14a), WetFix N (Fig.14b) and WetFix BE (Fig.14c) improved the coating of bitumen on the mineral substrate.
17
Fig. 14. Bitumen (Pen.70/100) droplet coalescence on the granite surface at 50 o C in a water phase containing emulsifier (R-Tallow Ethoxylated Diamine) and adhesion promoters at
pH=2.3, a) Diamine OLBS, b) Wetfix N, and c) Wetfix BE.
A qualitative comparison has been made, based on the experimental results, for instance, poor, strong or no adhesion in the water phase consisting of selected surfactant types and adhesion promoters.This kind of behavior may be linked to the critical micelles concentration (CMC) of the emulsifier in the water phase. Surfactants spontaneously aggregate in water and form welldefined structures such as spherical micelles, cylinders, and bilayers. The surface tension
decreases strongly with increasing concentration of surfactants in the water phase (see Fig.15). At a certain concentration, the critical micelle concentration (CMC), the surface tension becomes constant and above the CMC, surfactants spontaneously form micelles. The hydrocarbon chains gather inside the micelle and the polar head groups orientate towards the
aqueous phase [24]. In this work, all the selected concentrations of the prepared water phases containing emulsifiers were above the CMC. There is a further discussion about adhesion mechanisms at the end of this section.
Khan, Redelius, Kringos
18
Fig. 15. IFT as a function of emulsifer concentration (%) in the water phase and coalescence and adhesion of bitumen (Pen.70/100) droplets on the granite surface at indicated concentrations.
Fig. 16. Bitumen (Pen.70/100) droplet coalescence on the granite surface at 50 o C in a water phase containing emulsifier (R-Tallow Diamine) at pH=2.3, a) without adhesion promoters,
and with adhesion promoters b) Diamine OLBS, c) Wetfix N, and d) Wetfix BE.
Khan, Redelius, Kringos
19
The bitumen droplet coalescence test on a mineral surface was also carried out on a water phase containing 0.2% R-tallow diamine which did not have any ethylene oxide functional groups at pH=2.3, with and without adhesion promoters. The results are shown in Fig.16a-d, where (a) shows the results for the relaxation test without adhesion agent and (b-d) show the
results when adding diamine OLBS, WetFix N and WetFix BE to the water phase, respectively. The results are qualitatively similar to the previously investigated emulsifier Rtallow diamine ethoxylate as shown in Fig.14, but the kinetic reactions were slower.
Fig. 17. Bitumen (Pen.70/100) droplet coalescence on the granite surface at 50 o C in a water phase containing a) 1% Redicote E-47 NPF (nonionic emulsifier) at pH=7, b)1% Ampholak XCE at pH=11, (amphoteric emulsifiers behave as anionic emulsifiers at higher pH), and c) 1% Ampholak 7TX at pH=11.
The relaxation tests of bitumen droplets on a mineral surface were also carried out in the water phases prepared with non-ionic and anionic (amphoteric) emulsifiers (see Fig.17). The results show that with the non-ionic emulsifier, droplets relaxed very quickly as compared to the anionic (amphoteric) emulsifiers. In all cases without using an adhesive agent, bitumen
droplets did not stick to the mineral surface in the presence of water. However, bitumen droplets made a very good adhesion bond to the stone surface in the presence of adhesion agent in the non-ionic soap solution, as shown in Fig. 18. However, in the case of the anionic emulsifier, there was no such effect even after adding the adhesion agent to the water phase
soap solutions.
Khan, Redelius, Kringos
20
Fig. 18. Bitumen (Pen.70/100) droplet coalescence on the granite surface at 50 o C in a water phase containing adhesion promoter Diamine OLBS (0.02%) and a) 1% Redicote E-47 NPF (nonionic emulsifier) at pH=7, b) 1% Ampholak XCE at pH=11, (amphoteric emulsifiers
behave as anionic emulsifiers at higher pH), and c) 1% Ampholak 7TX at pH=11.
The adhesion mechanisms
In this study, it was noticed that bitumen droplets in an emulsion environment with/without adhesion promoters behaved differently. In the presence of emulsifiers, bitumen droplets did not adhere to the granite surface. However, the addition of 0.02% adhesion promoters to the water phase resulted in good adhesion. The reason adhesion promoters work is likely that the affinity of adhesion promoters towards the stone surface is stronger. Additionally, it is commonly believed by the surface chemistry experts that the adhesion mechanism is mainly based on adsorption of both emulsifiers and adhesion promoter’s molecules that move to the mineral surface. There could be two possible explanations for the adhesion mechanism of
emulsion systems without adhesion promoters. I) Emulsifiers keep their micelle shape before reaching the stone surface, but they collapse upon adsorption and form single or multilayered films on the stone surface. In case of single layer or at lower emulsifier concentration (below CMC) there could be an adhesion between bitumen droplet and a stone surface. But, in case of double or multilayered (above CMC), these surfactants create a repulsion barrier with the ones covering the bitumen drops or prohibit the direct contact between the mineral surface and the bitumen droplets (see Fig. 19a). II) A multilayered film would prevent adhesion, if the water and salts adsorb more strongly to the mineral surface than the emulsifier; then there will
be no adhesion. Molecules of surfactants and adhesion agents compete to sit on the mineral surface. Due to their smaller size, molecules of adhesion promoters cover the mineral surface faster than the emulsifiers, which are pulled back to the oil phase due by their long hydrocarbon chains. The molecules of adhesion promoters form a layer allowing bitumen molecules to settle and bond with the mineral surface (see Fig. 19b).
Khan, Redelius, Kringos
21
Fig. 19. Proposed mechanisms for adhesion between bitumen-mineral surface in the presence of a) emulsifier and b) emulsifier and adhesion promoter.
As with the surfactant molecules, the structure of adhesion promoters consists of a hydrocarbon chain and a functional group, usually an amine. These are typically prepared from the higher molecular weight ethylene amines and fatty acids. These molecules work as a contact bond between the hydrophilic aggregate and the hydrophobic bitumen. The amine group reacts with the aggregate surface, whereas the hydrophobic hydrocarbon chain interacts with the binder through interdiffusion. Moreover, the length of the hydrocarbon chain is an important factor in both the emulsifier and the adhesion promoter.
Materials properties, such as the specific surface area, the surface free energies of minerals and the acid/base interactions, could be controlling parameters for wettability and adhesion
between bitumen and aggregates [27, 28].
5. Conclusions
The research showed that the presence of emulsifiers in the water phase inhibits the adhesion of bitumen droplets to the mineral surface. However, very small additions (0.02%) of
adhesion promoters reverse the situation completely, and adhesion, rather than cohesion, is the dominating factor. This is valid under the experimental conditions in this investigation.
Experience from fully cured CMA show generally better adhesion than HMA with the same binder.
Based on research shown in this paper, it is recommended that the fundamental mechanisms and material properties that control the breaking and coalescence process in bitumen emulsions are further identified. This could lead to detailed coalescence control functions and parameters in bitumen emulsion technology and cold mix design. This, in turn, could provide the asphalt community with some better methods and tools to overcome the existing issues with CMA and overlap or completely replace the traditional old alternatives.
Acknowledgement
This research work was sponsored by Nynas AB and carried out at KTH Royal Institute of Technology, Sweden as well as at Nynas Bitumen Laboratory. Moreover, the authors would like to thank AkzoNobel Sweden for providing materials for testing. The authors acknowledge Måns Collin for scientific discussion and Nathaniel Taylor for proof reading.
(a)
Wetfix adhesives and Redicote emulsifiers are used for the production of bituminous emulsions, for asphalt in road construction and bituminous emulsions acting as preservation for buildings, among others. See our recommendations for the various applications shown in the overview
Wetfix BE
Liquid bonding agent for passive adhesion with good temperature stability at reasonable prices
Abstract
Requirements for properties of bituminous binders are determined in the European standards. The physico-chemical behaviour of bitumen depends on its colloidal structure (asphaltenes dispersed into an oily matrix constituted by saturates, aromatics and resins) that depends primarily on its crude source and processing. Bitumen properties are evaluated by group composition, elementary analysis, but more often conventional or functional tests. Bitumen for road uses is assessed according to the physical characteristics. For the purpose of improving the qualitative properties of bitumen and asphalts the additives are applied e.g. to increase elasticity, improving the heat stability, improving adhesion to aggregate, to decrease viscosity, increasing the resistance to aging, to prevent binder drainage from the aggregate surface, etc. The objective of presented paper is to assess and compare effect of additives on properties of bitumen binders. In paper, the results of bitumen properties, penetration, softening point, and dynamic viscosity of two paving grade bitumen 35/50, 50/70 and polymer modified bitumen PmB 45/80-75 are analyzed and also the changes of these properties by the application of selected additives (Sasobit, Licomont BS100, Wetfix BE and CWM) to improve adhesion to aggregate and improve workability. Measurements of properties have been performed according to the relevant European standards. The laboratory tests showed significantly increasing the softening point of paving grade bitumen 50/70 and 35/50 by 13 to 45°C. The effect of various additives on bitumen softening point is different. Penetration varies according to type of bitumen and type of used additive. The penetration values of modified bitumen PmB 45/80-75 with additives Sasobit and Licomont BS100 show increase of bitumen stiffness of 16 0.1mm and a shift in the gradation. The changes in penetration and in softening point significantly shown when calculating on Penetration index as a parameter of temperature susceptibility. The additives changed the viscosity of bitumen to lower values mostly with modified bitumen. In case of the additive Wetfix BE mix in 35/50caused the viscosity increase. The additive changes the properties of original bituminous binders, and that can affect the properties of asphalt mixtures and asphalt layers.
Czech Technical University in Prague, Faculty of Civil Engineering, Thakurova 7, Praha 6 – Dejvice, 166 29, Czech republic
Abstract
Bitumen-aggregate adhesion is one of the crucial characteristics related to an asphalt mix. It affects the mix durability mainly interms of its moisture susceptibility. Wide range of adhesion promoters is available to the market and can be used in regular practice, nevertheless usually only limited attention is paid to the long term activity (mainly the effective substances) and stabilityof the additives in the bitumen and the asphalt mix. Research done at the Czech Technical University in Prague is focused on
studying the impact of differently aged asphalt mix using selected procedures defined in prEN 12697-52 as well as developing aself-defined procedure by applying the PAV equipment used since many years for long-term bitumen ageing. The results of aged mixtures were always compared to unaged control mixes. In parallel use of aged bitumen was assessed as well. The results were further compared to a simple adhesion test to get a more complex understanding of the activity of selected additives. In total
more than 5 additives were selected and tested on one type of asphalt concrete with the application on a more hydrophilicaggregate type. Results gained during this experimental study are presented in the paper using as a criterion indirect tensile strength ratio determined either by EN 12697-12 or by modified procedure according to AASHTO T283.
In parallel because of elevated temperatures used during ageing suitable covering of cylindrical test specimens was analyzed as well to avoid unnecessary deformations or even disintegration of the tested specimens. For this reason two types of protective collar were chosen – PVC and thin steel mash – in both cases fixed by plastic belts. It is assumed that steel mash can better simulate the effect of ageing keeping the envelope partly free for direct contact with hot air and pressure. Results of this
comparison are presented in this paper as well.
1. Introduction
Prevalent part of the road infrastructure is built with asphalt mixes. However, similarly to any other built structure, also asphalt pavements change their properties and performance with time. Deterioration caused by moisture is seen as one of the key reasons of asphalt pavements deterioration, whereas for their maintenance and rehabilitation are European-wide yearly expended considerable financial means. The moisture can in general act on
adhesion loss what is the starting point of many pavement failures. Therefore moisture susceptibility of asphalt mixes is a critical aspect which has to be always evaluated. The typical mechanism of deterioration caused by moisture is reduced adhesion because of water which transfused to the interface of bitumen film and aggregate particle. Then stripping effect of asphalt coating usually starts up to release of particular aggregate particles. The
pace of this deterioration is significantly affected also by asphalt mix ageing. It is therefore important to reflect this natural process typical for bitumen if moisture susceptibility is assessed, especially if for reasons of improved adhesion various surfactants are used. To design asphalt mix resistant to water immersion and adhesion problems surfactants are usually added either to the bitumen or to the mix during its production. Their mission is to reduce the
hydrophilic behavior of the aggregates. Nevertheless, long term effect of these additives is exactly not known and is subject to many expert discussions. It is further questionable if these additives always deliver the solution for issues induced by moisture in all materials and for all necessary construction processes.
Main objective of the experimental study done by CTU in Prague was the development of suitable procedures for laboratory assessments of asphalt mix durability including the obtaining of knowledge with long term behavior of asphalt mixes in terms of their durability studied by indirect tensile strength test. The effort was to develop a simple and suitable test protocol which would simulate ageing (caused by known factors like oxidation, elevated
temperature and UV radiation) and impact of water and frost. At the same time it should simulate conditions of the real paved asphalt layer (compacted specimens with access of air and temperature). To forecast exactly the behavior and properties of aged pavement is as good as impossible because of enormous set of different variables. The study therefore compared suitable experimental methods for asphalt ageing simulation. Use of a suitable test protocol,
which would in a best way simulate these conditions, would deliver corresponding experience for determining the asphalt mix durability. During the research stage of this study standardized test methods for either bitumenaggregate adhesion or moisture susceptibility assessment were used. For ageing it should be stated that this phenomenon is today widely used for bituminous binders. In opposite to that ageing simulation for asphalt mixes is still an area with a lot of discussion and therefore with limited development of commonly acceptable test procedures – even if it is highly important to implement ageing if describing the functional characteristics and performancebased behavior of asphalt mixes.
2. Ageing
Over 30 methods of ageing for either bulk asphalt mix or compacted asphalt test specimens have been developed in the recent decades. For those, the material is usually stored under higher temperature (30 °C to 100 °C) for a stipulated number of hours, days or weeks which is intended to accelerate the oxidative processes caused by atmospheric oxygen. In some cases, pure oxygen or ozone is used as oxidising agent, while elsewhere additional
overpressure is applied to speed up the reaction. The ageing methods allow simulating a condition of long-term ageing in several days, thus presenting a situation closely resembling the effect on the layer within the pavement structure after several years. So ageing occurs in two phases, on a short-term scale and, then, subsequently, as longterm ageing. Long-term ageing depends on the short-term ageing; therefore, mix preparation and paving must be
performed as well as possible to render the mix less susceptible to ageing over the life-time. In the course of shortterm ageing, lightweight compounds evaporate and oxidation occurs during construction. With long-term ageing, steric hardening occurs and the pavement oxidizes over its entire life. The oxidation effect is an irreversible
chemical change. Steric hardening, contrastingly, is reversible as it involves a structural re-organization produced by
thermal change impact.
In the presented study four types of long-term ageing laboratory procedures were compared, including following
770 Tereza Valentová et al. / Transportation Research Procedia 14 ( 2016 ) 768 – 777
conditions:
x Placing bulk asphalt mix at temperature of 85 °C for 9 days in a thermal chamber; x Conditioning asphalt test specimens at temperature of 85 °C for 5 days;
x Ageing of specimens at elevated temperature of 85 °C and a pressure of 2.1 MPa in PAV for 20 hours; x Ageing of the bituminous binder applying the short-term ageing TFOT method (3x FTOT).
Within the framework of this study, the simulation of compacted specimen ageing is based on the ageing of the bituminous binder itself in PAV. First, the test specimens are wrapped in a steel mesh that is fastened by assembly ties according to Fig. 1 – wrapped specimen. This keeps the skeleton of the specimen unchanged even under higher pressure and temperature, avoiding deformation which might negatively affect the resulting strength. The prepared
specimens are then put on steel plates and gradually placed in the rack according to Figure 1. The rack is then put in the chamber where the specimens are heated up to 85 °C. Once the temperature is reached, the pressure is increased up to 2.1 MPa and maintained for 20 hours.
Fig. 1 (a) test specimens in protective collar in holder for testing in a Pressure Ageing Vessel (PAV); (b) detail of test specimens in protective collar by steel mesh.
3. Input material analysis and mix design
3.1. Input materials
Within this study straight-run bitumen 50/70 fulfilling requirements of CSN EN 12591 was used. For particular tests – mainly the bitumen-aggregate adhesion test according to CSN 73 6161 – several aggregate types have been selected differing in their mineralogy. These aggregates are normally used in the Czech Republic for asphalt mix production. Their specification is summarized in [Valentová 2016]. Based on more detailed analysis one type was
later experimentally selected based on characteristics and known mineralogical composition. This selected aggregate type was used for laboratory mix design and moisture susceptibility tests. To guarantee durability of the mix, some types of aggregate are more or less suitable from the point of view of adhesion between the bituminous binder and the aggregate. To meet the condition of active adhesion, the aggregate
must be free of any water to achieve perfect adhesion to the bituminous binder. In contrast to the bitumen, aggregate is often hydrophilic; this means that it absorbs water easily. The following adhesion promoters were used: Impact 8000 with 0.30%-wt. of binder, AdHere LOF 65-00 (0.30%-wt.), Zycotherm (0.10%-wt.), Wetfix BE (0.3%-wt.).
a) b)
Tereza Valentová et al. / Transportation Research Procedia 14 ( 2016 ) 768 – 777 771
Last but not least mechanical-chemically activated micro-filler originating from the Palestine limestone powders was chosen to act as an intelligent replacement for traditional fillers. It is a dehydrated sludge from limestone marble cutting, further modified by grinding in a special type of high-speed milling machine (disintegrator).
3.2. Input materials
For assessment of ageing impact on durability and adhesion an optimized ACbin 16 mixture was used. Clinkstone aggregates from the quarry Chlum were used known for worse adhesion behavior. The mix design is presented e.g. in [Valentová 2016].
4. Test definition
4.1. Determining adhesion between the binder and aggregate
In the Czech Republic, non-harmonized test according to CSN 73 6161 has traditionally been used to describe the adhesion. It uses a sample of heated aggregate (8/16mm), weight of 300±3 g and binder of 12±0.3 g at a temperature defined depending on the bitumen gradation (160±5 °C for aggregates and 170±5 °C for 50/70 bitumen). After the bitumen coated aggregates are cooled down for 24 hours, the sample is conditioned in water at 60±3 °C for 60 minutes. As soon as the sample has been removed from the water, the coating of aggregate particles is assessed visually and classified according to CSN 73 6161. In this study soliciting comparison with EN 12697-11, test method described in part C was not done.
4.2. Determining the test specimen moisture susceptibility
For the determination of moisture susceptibility usually strength ratios like ITSR (indirect tensile strength ratio), as given in EN 12697-12 are used to assess the effects of water on asphalt mixtures and define its durability. At the same time, the European test was further modified according to the American AASHTO T283 test method which, besides other compaction levels, also introduces specimen saturation with water as well as the application of a single freezing cycle; therefore, two negative effects – water and frost – are combined.
5. Results of the research
5.1. Evaluation of the adhesion test
The adhesion test between bitumen and aggregates involved 8 different types of aggregate and one bitumen representative improved subsequently by chemical adhesion promoters. To verify the effects of adhesion promoters and the effect of storage time, the variants of binders were subjected to short-term ageing (TFOT) according to CSN EN 12607-2. The binder was exposed to ageing effects for three times 5 hours at 163 °C. Table 1 summarises the results of unaged binder which indicates the results of one version with reference binder only and the results of a combination with a selected adhesion promoter for each aggregate type. The results were assessed as unsatisfactory for the bitumen without additives and aggregate from Chlum (clinkstone) and Zbraslav (mixed rock: ash rock, metatuf and spilite). The worst results were recorded for aggregate from the Kobylí Hora quarry (granulite), where only 35% of the aggregate remained coated by the bitumen after the adhesion test. The aggregates from 0DUNRYLFH /LERGGLFH 0CUXQLFH Dnd =EH?QR scored as satisfactory; the percentage of aggregate particle coating amounted to roughly 80%. The best result was scored when aggregate from the Litice quarry (spilite) was used; in this case the surface of the aggregate was stripped in approx. 10%, this means good affinity between the binder and the aggregate. The positive effect of the additives could be proven for all types of aggregate. On average, the percentage of coated surface of the aggregate increased by 10% when each individual additive was applied. The additives had the greatest effect on aggregates from Kobylí Hora, Chlum and Zbraslav, which failed the adhesion test without an additive. In these cases the adhesion improved by 20-30%. With the remaining specimens, adhesion improved as well with the only exception of the aggregate from Litice, which scored excellent results even without 772 Tereza Valentová et al. / Transportation Research Procedia 14 ( 2016 ) 768 – 777 the additive. A higher dose of additives resulted in a slight improvement of adhesion of the individual aggregate variants; or at least the adhesion did not deteriorate. The only exception was the higher dose of adhesion additive AdHere 65-00 LOF EU, where adhesion deteriorated; however, a repeat measurement was recommended for this case.
Focusing on the comparison of the aged binder, the results are arranged logically (Table 2) as in the preceding case. As is obvious from the measurements, contrary to expectations, ageing has a positive effect on the adhesion of bituminous binders to aggregate. Based on the majority of results, it can be noted that the level of aggregate particle coating by bitumen improves, or the remaining specimens do not demonstrate a deterioration of adhesion. In the case of the reference sample with bitumen 50/70, using the aggregate from Kobylí Hora and Zbraslav, the coatinglevel improved due to the influence of ageing time. In contrast to unaged bitumen, it is visible that the level ofcoating is going from satisfactory to excellent in the case of aggregate from the Chlum quarry.
Table 1. Results of adhesion test according to CSN 73 6161 for unaged bitumen.
Tereza Valentová et al. / Transportation Research Procedia 14 ( 2016 ) 768 – 777 773variants of the mixes unaffected by ageing, the following findings can be highlighted. The reference mix reached the indirect tensile strength of 2.39 MPa. The mix variant using a mechanical-chemically activated micro-filler scored almost the same result as the reference mix. The diagram also shows that the application of adhesion promoters decreased the indirect tensile strength in comparison to the reference mix. The greatest reduction by 0.48 MPa in comparison to the reference mix was observed for the variant with Zycotherm and in the case of a higher dose of Impact 8000. However, the difference could have been caused by insufficient tempering of the test specimens. As suggested by the latest results of a partial research just completed, testing indirect tensile strength at different temperatures showed an increase of the strength on average by 17.5% if the test temperature was by 2 °C above the prescribed temperature of 15 °C; on the other hand temperature by 2 °C below the prescribed value reduced the strengths by 3,8%. It is obvious that even the slightest change in testing temperature affects the results as such. The second columns (black shading) represent the ITS of test specimens where the first method of laboratory ageing was applied. The method consisted of preparing Marshall test specimens which are then put in a climatic chamber with forced circulation at 85 °C for 5 days. As is obvious from the results, strength of the reference mix and of mix with a higher dose of AdHere additive showed lower strength than unaged mix; for the remaining mixes, the indirect tensile strengths increased which was one of the assumptions. Comparing the results of aged test specimens, the mix with Zycotherm and micro-filler demonstrate higher strengths than the reference mix (by 0.28 MPa and 0.40 MPa,respectively). The remaining values are similar, or lower on average. Fig. 2. Comparison of indirect tensile strengths of test specimens left in air. The third columns (white shading) indicate the results of the second method of laboratory ageing where the asphalt mix was distributed evenly on a pre-prepared mat where the mix was aged in the climatic chamber withforced circulation at 85 °C for 9 days. When the time was up, test specimens were compacted fo each mix by compactor (2×25 blows) and subsequently used to determine moisture susceptibility. The third series of results shows that the reference mix had the highest indirect tensile strength of 2.68 MPa, the mix with micro-filler and Zycotherm scored almost identical result. For the other mixes, the results of indirect tensile strength were lower when compared to the reference mix. When the variants were compared to one another, it is obvious that the ageing of bulk asphalt mixes affects the subsequent test specimen compaction and strengths in comparison to unaged test specimens where they score 10% more (or, in the case of Zycotherm, about 35%). The ageing of test specimens as such does not demonstrate the same tendeny in all cases which might be caused by the laboratory ageing method applied where the specimens are placed in a climatic chamber at higher temperature; this might cause deformationand the specimens may lose the original volume. Last column shows indirect tensile strength values for test specimens which were laboratory aged by the PAV method at elevated temperature and pressure. In comparison to the previous test methods of simulated ageing it is obvious that considerable drop in ITS values was reached mainly for control mix and mix with filler substitution. In the case of mix option with higher content of adhesion promoter AdHere and Wetfix the results after PAV ageing 774 Tereza Valentová et al. / Transportation Research Procedia 14 ( 2016 ) 768 – 777 are close to the ITS values gained also during the remaining laboratory ageing test procedures. In these cases only minimum drop in ITS values was gained. 6.2. Evaluation of moisture susceptibility of test specimens, including one freezing cycle The effect of adhesion promoters on asphalt mix resistance to negative effect of water was compared for all seven mix options. The results of the testing according to EN 12697-12 are represented graphically in Fig. 3-5. The results were viewed from several perspectives. The first question concerned the effect of the adhesion promoter applied from the point of view of moisture susceptibility, i.e. whether the ITS ratio improves or not. It was also assessedwhether the indirect tensile strength ratios meet the minimum required value as stipulated by the national annex to standard CSN EN 13108-1 for asphalt mixes ACbin (at least 80%). If evaluating test specimens exposed to adverse effects of water with one freeze cycle neither US standard AASHTO T 283-03 nor the national annex to standard CSN EN 13108-1 stipulates a minimum ITSR threshold. For the purposes of experimental comparisons, such threshold was set to 70% within this study. When indirect tensile strengths of unaged specimens (see Fig. 2) were compared, it could be noted that the specimens exposed to adverse effects of water reached the threshold of ITSR = 0,80 in almost all variants. Focusing on comparison of individual variants, the mixes with higher content of AdHere 65-00 LOF EU recorded a reduction in ITSR to 0,65. Contrary to the expectations, the results demonstrated that, the pplication of adhesion promoter had no effect on improving moisture susceptibility in comparison to the reference mix. The conclusions are confirmed by the values measured in test specimens exposed to adverse effects of water, including the freezing. In that case, the ITSR was set to 0,79 for the reference mix; the same was achieved by the variants with micro-filler and Zycotherm or Wetfix BE. For the remaining variants, the indirect tensile strength ratio decreased almost to 70% which was determined as the threshold.
Fig. 3. Results of ITSR test; unaged asphalt mixes. Fig. 4. Results of ITAR test; aged asphalt test specimens 5d@85 °C. Fig. 4 gives an overview of the ITSR results for test specimens exposed to ageing for 5 days at 85 °C. Focusing on the ITSR according to CSN EN standard, it can be noted that the best results were achieved by the variant with a higher content of AdHere 65-00 LOF EU. The ITSR amounts to nearly 0.98 while a similarly high value was achieved by the AASHTO method although the procedure is based on less favourable conditions affecting the asphalt mix under observation. The mix option with micro-filler reached a 0.85 limit which meets the minimum threshold required. Out of the remaining mixes, the variant with a lower proportion of AdHere and the variant with Impact come close to the threshold. It is obvious that a higher dose of the additive with the aggregate concerned has no potential to improve moisture susceptibility as is also confirmed by the results according to AASHTO method. The poorest results in ITSR were recorded by the asphalt mix with Wetfix where the ratio came to 0.37 for the European approach and 0.29 for the American test method, i.e. almost fifty per cent less than the value of the eference mix. The aforementioned result is at least noteworthy; it might point out some restrictions of the test When compared to Wetfix, the variant with Zycotherm scored better (0.52 vs. 0.40); however, the mixes do not meet the required minimum ITSR thresholds anyway. Focusing on the results of test specimens made of aged bulk asphalt mix, the results in Fig. 5 are of interest. The moisture susceptibility results determined according to CSN EN methods and the US test method yield almost identical ITSR values, despite the fact that the latter method exposes the test specimens to less favourable conditions. When compared to the reference mix where the ITSR amounts to 0.71 and 0.68, we can note that neither Impact 8000 in a content of 0.3% and 0.6%, nor Wetfix delivered any improvement in adhesion; the ITSR ratio amounts to 0.60 on average. An improvement was recorded in the case of micro-filler application and for AdHere content of 0.3%. In these cases, the ITSR amounts to roughly 0.90. Higher content of AdHere resulted in further improvements.
6.3. Results of PAV asphalt mix ageing
Ageing of test specimens at elevated temperature and pressure in PAV apparatus had essential impact on indirect tensile strength values. In opposite to remaining used methods of simulated ageing the test specimens in this case were subjected to less favorable conditions. Overall they might maybe better simulate the impacts of adverse conditions during the entire life-time of an asphalt mix in a pavement. If focusing on comparison of test specimens with respect to moisture susceptibility according CSN (see Fig. 6), it is obvious that selected options reach more or less in all cases the required limit of ITSR = 80%. The only exception is asphalt mix containing Zycotherm additive, where the ITSR value was 0.74. Second column demonstrates results of indirect tensile strength ratios according to modified AASHTO test procedure. The lowest values were gained again in the case of asphalt mix with Zycotherm, but surprisingly also for higher addition of Impact promoter, where the ITSR reached only 0.66. All remaining mix options reached a minimum value of 70%, whereas the best results were shown for the option containing pulverized filler from Palestinian limestone (0.90) as well as for mixes with AdHere (0.83) or Wetfix (0.81) adhesion
promoters.
Fig. 5. Results of ITSR test; aged bulk asphalt mix 9d@85 °C. Fig. 6. Results of ITSR test; PAV 20h@85 °C, 2.1 MPa. 6.4. Comparison of different test specimen covering for ageing in the tempering chamber under higher temperature As has been mentioned in Chapter 2.2, this study has also examined the effect of a higher temperature, i. e. 85 °C, when the test specimens were placed in the tempering chamber for 5 days during the ageing process. To evaluate the effect of the thermal conditioning on specimen dimensions three sets of specimens were prepared within the framework of the test; the first set was placed freely in the tempering chamber. For the second set, a protective collar was made with a PVC cover and ties to avoid deformation due to temperature. In the case of the last set of specimens, the PVC cover was replaced by a steel mesh which was supposed to simulate the real-life conditions 776 Tereza Valentová et al. / Transportation Research Procedia 14 ( 2016 ) 768 – 777
better with respect to air access in the tempering chamber not only from the top and bottom of the specimen but also from the sides to ensure its even ageing. Both types of test specimen cover are documented in Fig. 7.
Fig. 7 (a) The test specimen with a protective collar created by a steel mesh and tightening straps; (b) test specimens with a PVC case. The effect on asphalt mix bulk density was observed for the test specimens. For the sake of simple comparison indirect tensile strength was determined for all the specimens. The results are summarized in Table 3.
Table 3. Results for test specimen in different a protective collar – aged specimen 5d@85 °C.
Mix type Mix acronym ITSdry
Standard
deviation ITSR C SN EN
Standard
deviation IT SRAASHTO
Standard
deviation
For both selected mixes, the impact on moisture susceptibility as depicted in Tab. 3 was monitored, too. The best results of indirect tensile strength ratios were achieved when steel mesh was applied. In this case, the test specimens are allowed to age evenly, air circulation facilitates even ageing just like in the case of freely placed specimens; however, when the mesh is used, there are no further deformations or disintegration. Covering the specimens with PVC prevents air access in the tempering chamber with forced air circulation and the specimens thus cannot age evenly. The results allow assumptions on the positive effect of a protective steel mesh collar; however, the ageing of test specimens in PAV plays a significant role in the method since it takes into account, besides the higher temperature, also the pressure which has a much less positive impact on the test specimens (they are much more susceptible to deformation, or complete disintegration).
Conclusions
The issue of adhesion between aggregate and bituminous binders as well as the closely related aspect of durability tested by asphalt mix resistance to water remains one of the longest studied asphalt mix phenomena. Similarly to the ageing of bitumen and asphalt mixes, we still cannot describe and verify all phenomena affecting the adhesion as such with clarity and certainty since there are both physically-mechanical and chemical aspects of the issue as such. Moreover, if the two phenomena are combined they allow us to reflect the real-life conditions much better; however, the problem becomes more complex at the same time.
The presented study delivered results which make it obvious that the used adhesion test provides quick information on the quality of aggregate particle coating by bitumen; the disadvantage is its considerable dependence a) b)
on the evaluator’s subjective impression and the fact that the method applied is quite difficult to relate to any reallife effects in the pavement structure. The subjective evaluation aspect can surely be eliminated by more exact and more demanding methods (e.g. determining the contact angle), the problem of making the test conditions more realistic should be taken into account at least by considering the ageing aspect, but also by the possible effects of not
only the water-elevated temperature combination but a more complex water-frost-temperature-time approach. Due to that, we tried to take into account at least the time (and ageing) factor in the partial assessment. This can help to at least indicate the stability of surfactant effects.
The issue of asphalt mix ageing and water susceptibility is similarly complex. Firstly, we have to say that regardless of the interpretation of what period is simulated by the specific ageing method, it is appropriate to assess aged asphalt mixes. The effect undoubtedly occurs in the pavement structure and it is unimportant, from the perspective of life and effect of the adhesion promoters, what occurs e.g. during the first year; the important thing is
how effective it will be on the overall asphalt mix behaviour after 5 or more years. The ageing of compacted test specimens is probably better in simulating the actual situation in the pavement although, on the other hand, the level of compaction of the asphalt mix within the pavement is higher than the selected approach with 2×25 impacts which is considered for the purposes of simulating accelerated water effect. In the case of bulk asphalt mixes, the results
seemed more consistent; this approach to ageing is simpler to perform and the test specimens are not deformed at all. On the other hand, the bitumen film ages evenly throughout the mix; this does not reflect the likely situation of a compacted asphalt layer. Therefore, what is simulated by this approach is a matter of interpretation. Last but not least, particularly in areas where cold and hot climates alternate, a change of the existing methodology of moisture
susceptibility evaluation must be supported and a freezing cycle added to the test as this has an impact on the pavement structure and affects the durability of the asphalt mix.
Acknowledgement
emli Yüzey / Islak Zemin Yaptrcs
Ürün tanm :
Bostik WetFix, yüksek performansl, tek bileenli, nem ile kürlenen, MS polimer esasl yaptrcdr. Nemli yüzeyleri yaptrr hatta sualtnda bile kullanlabilir.
Kullanld yerler :
• Ahap, beton, tula, alç, cam, seramik, metal, sert PVC yaptrmada
• Yukarda belirtilen yüzeylerin balant panelleri, tabelalar, duvar kaplamalar ve süpürgeliklerin montajnda
Özellikler :
• Nemli ve gözenekli yüzeyleri bile mükemmel yapr.
• Kokusuzdur
• Büzüme yapmaz
• Kalc olarak elastiktir
• Çözücü içermediinden s yaltm plakas, dekoratif panellerin yaptrlmasnda da kullanlabilir.
• Üzeri boyanabilir.
• Polietilen, polipropilen ve teflon gibi yüzeylerde kullanlmamaldr.
• Bitüm bulam yüzeylerde kullanlmamaldr.
Emulsion recipes samples
Pot hole repairs – EBK-2.
Bitumen 60-65%
Adhesion additive Diamin OLBS or Wetfix BE – 0,05-0,1%
White spirit (kerosene, aviation fuel) – 0-1,5% (recommended)
Latex Butonal NS 198 – 1,2-2,5% (recommended)
Emulsifier Redicote EM 44 – 0,2-0,3%
Acid ??L (20-30%) – 0,15% on ?? factor 2,0-2,5 (phosphoric acid may be used)
Water
Surface treatment – EBK-2, EBK-1.
Bitumen – 67%
Adhesion additive Diamin OLBS or Wetfix BE – 0,05-0,1%
White spirit (kerosene, aviation fuel) – 0-1,5%
Latex Butonal NS 198 – 1,2-2,5%
Emulsifier Redicote EM 44 – 0,1-0,25%
Acid ??L (20-30%) – 0,15% on ?? factor 2,0-2,5
Water
Tack coat – EBK-1, EBK-2.
Bitumen – 50%
Emulsifier Redicote EM 44 – 0,15 %
Acid ??L (20-30%) – 0,15% on ?? factor 2,0-2,5
Water
SLURRY SEAL – EBK-3
Bitumen 100/130 – 57-62%
Cohesive additive Wetfix BE – 0,3%
White spirit (kerosene, aviation fuel) – 0,5-1,5%
Latex Butonal NS 198 – from 3,0 to 5,0%
Hydrochloric acid Orthophosphoric acid
Emulsifier Redicote 404 – 0,6-1,4% Emulsifier Redicote ?? 44 – 0,6-1,4%
Acid ??L (20-30%) – on ?? factor 2,0-2,5 Acid ?3??4 – on ?? factor 2,0-2,5
Water Water
THE STUDY OF OPERATING CAPACITY OF ASPHALT CONCRETE MODIFIED WITH AN ADDITIVE WETFIX BE.
Abstract: Statement of the problem. The problem of increasing the operating capacity of asphalt pavements is very urgent. The practice of road construction shows that after the start of the operation there is rut formation on an asphalt surface and various defects and deformations, one of the main reasons for that is unsatisfactory adhesion of bitumen with a paving stone. One of the applied solution methods is the introduction of various modified additives in organic astringent. This paper presents the results of the study of the main physical, mechanical and operational properties of bitumen and asphalt concrete modified using an adhesive additive Wetfix BE. Results. The paper presents a theoretical review of ways to increase the deformation stability of asphalt surface in high temperatures suggested by the authors. The results of the experimental studies are shown according to the estimation of the influence of adhesive additive Wetfix BE to physical, mechanical and operational properties of the bitumen SRC 60/70 and hot thick asphalt concrete BTN C12,5. Conclusions. The results of the experimental research allow one to make a conclusion that application of an adhesive additive Wetfix BE bitumen adhesion with paving stone improves, the deformation stability of asphalt surface in high temperatures increases. A significant positive effect was identified using an adhesive additive Wetfix BE in number of 0,2% on the bitumen mass for an increasing the operating capacity of asphalt pavements.
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Zastosowanie
WETFIX BE jest cieklym srodkiem adhezyjnym, opracowanym
specjalnie dla asfaltów mieszanych na goraco, kiedy wymagana
jest dobra odpornosc termiczna. Moze byc stosowany do 200 oC
w recepturach z asfaltami modyfikowanymi.
Sposób uzycia
Dozowanie WETFIXU BE zalezy od typu uzytego bitumu i kruszywa. Zazwyczaj dodaje sie 0,2 do 0,5% w stosunku do bitumu.
Czas kontaktu z asfaltem nie wplywajacy w znaczacy sposób
na polepszone wlasciwosci adhezyjne w zaleznosci od temperatury:
? do 100oC – bez ograniczen;
? do 140oC – 10 dni;
? do 170oC – 5 dni;
? do 190oC – 3 dni.
Wlasnosci fizyczne
? wyglad zewn. w 20oC brazowa lepka ciecz;
? gestosc w 20oC 980 kg/m3;
? temperatura plyniecia (oC) < 0oC;
? lepkosc w 20oC 3000 mP;
? lepkosc w 50oC 400 cP;
? temperatura zaplonu (oC) > 218oC (w otwartym plomieniu).
Specyfikacja
Parametr: Wartosc: Jednostka:
? calkowita liczba aminowa 159-185 mg HCl/g;
? liczba kwasowa < 10 mg KOH/g.
Pakowanie i przechowywanie
WETFIX BE jest dostarczany w bebnach stalowych (190 kg netto) i w paletopojemnikach (900 kg netto). Produkt jest stabilny
przez minimum 2 lata w oryginalnie zamknietych pojemnikach.
Srodki ostroznosci
Przy stosowaniu WETFIXU BE zaleca sie uzywanie okularów, rekawic i odziezy ochronnej.
Doradztwo techniczne
Minova Ekochem S.A. oferuje kompletne doradztwo techniczne
w zakresie stosowanych produktów i technologii.
Informacje dodatkowe
Minova Ekochem S.A. jest liderem rynku chemii górniczej specjalizujacym sie w dostarczaniu wysokiej jakosci produktów dla
górnictwa i budownictwa tunelowego, a takze dla budownictwa
mostowego, hydrotechnicznego i inzynieryjnego.
Produkty Minova Ekochem S.A. obejmuja nastepujace grupy:
wzmacnianie i uszczelnianie górotworu, wypelnianie pustek
w górotworze, pasy podsadzkowe, membrany natryskowe, kotwienie, naprawy konstrukcji zelbetowych, betony zalewowe,
betony natryskowe, zaprawy szybkosprawne, zestawy pompowe
i akcesoria oraz sprzet ochrony osobistej.
W ofercie znajduja sie równiez pozagórnicze poliuretanowe systemy surowcowe
Wetfix® BE
Benefits and Features
? Versatile product: Wetfix BE provides
both active and passive adhesion and
finds use in a wide range of bitumen mixtures and spray applications
? Value for Money: Wetfix BE is a concentrated product with consequent low dosage and low treatment costs
? Heat Stability: The performance is maintained after storage in hot bitumen.
? Low Volatility: The product does not
contain solvents and has low volatility at
hot mix temperatures.
? Easy to Use: The product has lower
viscosity than other concentrated antistrips
Dosage
Hot and Warm Mix 0.2-0.5% basis binder
Patch Mix, Soft Bitumen Mix 0.5-1.0% basis binder
Specification
Acid Value, mgKOH/g <10 VE 2.013
Amine value, mgHCl/g 160-185 VE 2.018
Physical Properties
Appearance at 25°C (77°F) liquid
Pour point, °C <-20(<-4°F)
Flash point , °C >218(>424°F)
Viscosity, mPa.s (cP) at 20°C (68°F) 800
Density, g/cc at 20°C (68°F) 0.98
Density, lbs/U.S.gal at 20°C (68°F) 8.18
Physical Properties are typical data based on our own measurements or derived from the literature. They do not constitute part of the delivery specification Adhesion Promoter for Hot and Warm Mix, and for cold and warm mix based on foamed bitumen, soft bitumen or cut-back. Adhesion promoter for hot applied chipseal.
Storage and Handling
Wetfix BE may be stored in carbon steel tanks. Bulk storage should be maintained at 10-40°C (50-105°F). Avoid heating above 65°C (150° F).
Wetfix BE contains amines and may cause severe irritation or burns to skin and eyes. Protective gloves and safety goggles must be used when handling this product. For further information, consult the Safety Data Sheet.
Packaging Information
Wetfix BE is available in bulk shipments, in tight head drums of 190kg (419lb) net weight, or in one-way totes (IBCs) of 900kg(1984lbs)
Notes
Redicote, Rediset, Kling, Perma-Tac, and Wetfix are registered trademarks in many countries.
No representation or warranty, expressed or implied, is made as to the accuracy or completeness of the information of data contained herein and AkzoNobel Surface Chemistry shall have no obligation or liability whatsoever with respect to any such information or data, including, but not limited to, any liability for infringement of patent or other industrial property rights. Surface Chemistry disclaims all implied warranties of merchantability and fitness for a particular purpose. Surface Chemistry shall in no event be liable for incidental or consequential damages, including, without limitation, lost profit, loss of income, loss of business opportunity and any other related costs and expenses.
GENERAL CHARACTERIZATION
CRALANE CAR 81 is an emulsifier for rapid and medium setting bitumen emulsions.
composition
quality control data
color red
delivery form liquid
state liquid
amine number value [mgKOH/g] 140-165
density(20 C) 0,85-1,0 g/cm3
additional product descriptions data
analysis of dry residue 100%
odine number value [g l/100g] 80-100
application
use
Cralane car 81 is a special surfactant based on fatty amidoamine derivative especially designed to emulsify bitumen.
dosage
the recommended dosage rates are between 0,25 and 0,5 % in relation to the emulsion.
technical application data
tests
emulbitumen colloid mill (Atomix) 9000rpm.
bitumen 150/200
emulsion (rapid setting):
63%bitumen
2% white spirit
0.25/0.35 emulsifier
transportation, handiling &storage
handling
please refer to material safety data sheet for details
storage conditions
it is recommended to store the product at room temperature and to protect it against influences of heat and frost
shelf life
subject to appropriate storage in closed original containers under the a. m. storage and temperature conditions, CRALANE CAR 81 is stable for at least 2 years.