Damping of Shear Vibrations in Asphalt Modified with Styrene-Butadiene-Styrene Polymer

Author(s):  
Jiri Stastna ◽  
Ludo Zanzotto ◽  
Otaca Vacin

Shear vibrations in conventional and polymer-modified asphalt binders are examined. Using dynamic compliances instead of moduli, viscous deformation effects can be separated from total deformation and the modified dynamic loss compliance and modified loss tangent functions can be defined. These two material functions appear to be more sensitive than viscoelastic moduli to the rheological behavior of asphalt binders and to changes caused by polymer addition. The characteristic temperature of the transition from the viscoelastic to viscous behavior of asphalt binder ( Tv) can be identified by using the viscous asymptote J”. The damping of shear vibrations that likely relates to the internal structure of asphalt material can be described by the modified loss tangent. The rheological behavior of the base asphalt 200/300 penetration grade and its blends with different amounts of radial styrene-butadiene-styrene rubber is investigated. Using master curves of dynamic functions and the Williams-Landel-Ferry form of the shift factor, isochrones of the original and modified dynamic material functions are constructed. Characteristic temperatures of the viscous transition ( Tv) and the glass transition ( Tg) are determined. Damping behaviors of the base and modified asphalts are studied.

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2888
Author(s):  
Sylwia Dziadosz ◽  
Mieczysław Słowik ◽  
Filip Niwczyk ◽  
Marcin Bilski

The paper presents the results of laboratory investigation on asphalt binders relaxation at low temperature, carried out in a ductilometer using the tensile test with continuous force measurement. Polymer modified asphalt binder samples consisting of a 50/70 penetration grade bitumen mixed with a concentrate of styrene-butadiene-styrene (SBS) modified bitumen—a 160/220 penetration grade bitumen modified with a SBS copolymer in the amount of 9%—were tested. Therefore, polymer modified binders containing 3%, 4.5%, 6% and 7.5% SBS, respectively, were obtained and investigated. Tensile tests were performed at −16 °C on samples before aging and subjected to short-term aging (RTFOT). Test results in the form of relaxation curves have been mathematically described using a modified generalized Maxwell model. Based on the acquired results, it was shown that the increase of the SBS copolymer content in asphalt binder precipitates the relaxation process, while aging slows down this phenomenon. It has also been proven that with increased content of SBS elastomer in asphalt binder, the effect of short-term aging on binder’s stress relaxation ability at low temperatures is reduced.


Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5715
Author(s):  
Bangwei Wu ◽  
Chufan Luo ◽  
Zhaohui Pei ◽  
Chuangchuang Chen ◽  
Ji Xia ◽  
...  

A wide variety of polymer additives have been widely used in recent years. However, the effect of different polymer additives on the durability of asphalt binders has not been investigated thoroughly. To evaluate the aging property of styrene-butadiene-styrene (SBS) asphalt binder with different polymer additives, three polymer modifiers, namely high modulus modifier (HMM), anti-rutting agent (ARA), and high viscosity modifier (HVM), were added to it. First, the Thin Film Over Test (TFOT) and Pressure Aging Vessel (PAV) was performed on the asphalt binders. The rheological properties of the four asphalt binders before and after aging were then checked by the Dynamic Shear Rheometer Test (DSR). The chemical compositions of the asphalt binders were determined by the Fourier Transform Infrared Spectrometer (FTIR) test. Several aging indicators were adopted to reflect the aging degree of the asphalt binders. The results show that when polymer additives are added to the SBS asphalt binder, the complex modulus, storage modulus, loss modulus, and rutting factor substantially increase and the phase angle decreases. All the test parameters become higher after aging. The phase angle of the SBS asphalt binder is the highest at both unaged and aged states, while its other parameters values are the smallest. Moreover, the Carbonyl Aging Indicator (CAI) of SBS with polymer additives becomes lower under both TFOT and PAV conditions, indicating that polymer additives can improve the aging resistance of SBS asphalt, of which HVM modifies the aging resistance best. Complex Modulus Aging Indicator (CMAI) and Storage Modulus Aging Indicator (SMAI) have the best correlation coefficients with CAI, and the two aging indicators can be used to predict the aging degree of polymer modified asphalt binders.


2021 ◽  
Vol 1036 ◽  
pp. 459-470
Author(s):  
Hong Gang Zhang ◽  
Qiang Huai Zhang ◽  
Xue Ting Wang ◽  
Hua Tan ◽  
Li Ning Gao ◽  
...  

A styrene-butadiene-styrene triblock copolymer (SBS) was grafted with an unsaturated polar monomer (monomer A) composed of maleic anhydride (MAH) and methoxy polyethylene (MPEG) via a ring-opening reaction after epoxidizing styrene-butadiene-styrene triblock copolymer (ESBS). The microscopic changes of SBS before and after grafting has been characterized with Fourier transform infrared spectrum (FT-IR), X-ray photoelectron spectroscopy (XPS) and gel permeation chromatography (GPC). The results revealed that the monomer A was successfully grafted on SBS backbone, and the maximum graft ratio (GR) was 20.32%. To verify the compatibility between SBS and asphalt, solubility parameters and surface free energy (SFE) of SBS, grafted SBS and asphalt were measured. It was found that the solubility parameter and SFE of grafted SBS were closer to asphalt compared with SBS. It also has been confirmed from storage stability that the temperature susceptibility of grafted SBS modified asphalt was reduced in compare with SBS modified asphalt binder. As consequence, the use of grafted copolymer can be considered a suitable alternative for modification of asphalt binder in pavement.


2008 ◽  
Vol 35 (9) ◽  
pp. 908-917 ◽  
Author(s):  
Soon-Jae Lee ◽  
Serji N. Amirkhanian ◽  
Khaldoun Shatanawi ◽  
Carl Thodesen

This research investigates the influence of compaction temperature on rubberized asphalt mixes and binders. For this, four Superpave mix designs for four asphalt binders (control, 3% styrene–butadiene–styrene (SBS)-modified, 10% rubber-modified, and 15% rubber-modified) were carried out. A total of 160 specimens were manufactured at four compaction temperatures of 116, 135, 154, and 173 °C. The binders were artificially short-term aged for 2 h at the mixture compaction temperatures prior to the binder tests. The results from this study showed that: (i) the control and SBS-modified mixtures could have almost the same air–void contents at a wide range of compaction temperatures; (ii) the compaction temperatures significantly affected the volumetric properties of the rubberized mixes; (iii) the aging difference of asphalt binder in the mixture depending on the compaction temperature is not considered to be a main factor affecting the volumetric properties of the mixtures.


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