THE INFLUENCE OF POLYMER ON RHEOLOGICAL AND THERMO OXIDATIVE AGING PROPERTIES OF MODIFIED BITUMEN BINDERS

2017 ◽  
Vol 79 (6) ◽  
Author(s):  
Nura Bala ◽  
Ibrahim Kamaruddin ◽  
Madzlan Napiah

Polymer modified bitumen (PMB) has been used for many years to improve the performance of asphalt concretes against premature pavement defects. In this research, modified samples were prepared with 2%, 3%, 4%, 5% and 6% Linear Low Density Polyethylene (LLDPE) polymer by weight of bitumen binder. The influence of LLDPE polymer was evaluated through binder properties test which includes penetration, softening point, storage stability, temperature susceptibility, rutting, fatigue and thermal oxidative aging resistance from a dynamic shear rheometer (DSR) measurements at a temperature of 20 OC to 60 OC. Results show that LLDPE polymer has a significant effect on binder properties. Penetration decreases and softening point increases with increasing LLDPE content on the modified binder after aging, which implies LLDPE improves the thermo oxidative aging resistance of the binder. Furthermore, the storage stability test shows that at higher LLDPE concentrations phase separation may occur. DSR analysis shows that modified binders have lower temperature susceptibility and higher aging resistance with increased stiffness and elastic behavior compared with unmodified binders. In addition, modified binders show enhanced resistance against high temperature rutting and at low temperature fatigue performance. It was found that the optimum LLDPE content is 6%.

2014 ◽  
Vol 505-506 ◽  
pp. 174-179 ◽  
Author(s):  
Ramez A. Al-Mansob ◽  
Amiruddin Ismail ◽  
Nur Izzi Md Yusoff ◽  
Che Husna Azhari ◽  
Mohamed Rehan Karim ◽  
...  

Polymer modified bitumens have tended to be the most popular among the various types of modified binders that are available worldwide. Polymer modification significantly alters the rheological characteristics of the binder, thereby requiring the use of fundamental rheological testing methods to provide an indication of the performance of the binder and subsequently the asphalt mixture. In this paper the characterization of bitumen modified with epoxidized natural rubber (ENR) was done with four percentages of ENR content. The effects of the modifier on the conventional properties, storage stability and rheological properties were investigated. The results indicated that storage stability of ENR modified bitumens (ENRMB) were mainly dependent on the ENR content. ENR reduced the temperature susceptibility. The degree of the improvement generally increased with ENR content up to 9%.


Bitumen modification is done to enhance the properties of bitumen related to elasticity, temperature susceptibility, softening point etc. This research intends to assess the effects of natural rubber latex (NRL) in liquid form as a bitumen modifier. Conventional tests, temperature susceptibility and phase separation due to hot storage were investigated using two separate mixing speeds of 1200 and 1300 revolution per minutes (rev/min). Morphology due to the addition of NRL has also been explored utilizing Atomic Force Microscopy (AFM). NRL was incorporated into the bitumen by weight of the binder for the modification at three different amounts (i.e. 3%, 5% and 6%). Based on the softening point, penetration value, temperature susceptibility and storage stability the latex-modified asphalt binder were analyzed. Results of the investigation showed that owing to enhancement in viscoelastic properties, the latex-modified asphalt binder will not undergo phase separation during hot temperature storage. Meanwhile, a uniform dispersed network was indicated by the morphological analysis with the presence of three phases of para, peri and cata. It can be deduced from the results obtained that the latex-modified asphalt binders will perform better in terms of softening point, penetration value and susceptibility due to temperature.


2018 ◽  
Vol 80 (4) ◽  
Author(s):  
Ebenezer Akin Oluwasola ◽  
Mohd Rosli Hainin ◽  
Mohd Khairul Idham ◽  
Modupe Abayomi

The failures of the flexible pavements are not only caused by harsh climatic conditions prevailing in most of the tropical countries but also due to increase in traffic. The ethylene vinyl acetate (EVA) modification of the bitumen can strengthen the properties of binders and also improve the quality of bitumen used for pavements construction. This paper reports the changes in physical and rheological properties of unaged 80-100 grade bitumen modified with different percentages of EVA and compared with the properties of PG 76 binder. The penetration, softening point and viscosity properties were studied. The rheological properties were measured using dynamic shear rheometer and the test was performed at temperatures ranging from 46 to 76 ⁰C at intervals of 6 ⁰C. It was noted that, after modification, the properties of binders had improved. The results show that 5% EVA content by weight in modified binder is adequate in terms of physical and rheological properties studied. In addition, the properties of 5% EVA modified 80-100 grade bitumen are similar to PG 76 binder.


2021 ◽  
Vol 13 (19) ◽  
pp. 10582
Author(s):  
Peng Wang ◽  
Hong-Rui Wei ◽  
Xi-Yin Liu ◽  
Rui-Bo Ren ◽  
Li-Zhi Wang

The thermal storage stability of styrene–butadiene–styrene tri-block copolymer modified bitumen (SBSPMB) is the key to avoid performance attenuation during storage and transportation in pavement engineering. However, existing evaluation index softening point difference within 48 h (ΔSP48) cannot effectively distinguish this attenuation of SBSPMB. Thus, conventional physical indexes, rheological properties, and micro-structure characteristics of SBSPMB during a 10-day storage were investigated in this research. Results showed that during long-term thermal storage under 163 °C for 10 days, penetration, ductility, softening point, recovery rate (R%), and anti-rutting factor (G*/sinδ) were decayed with storage time increasing. This outcome was ascribed to the phase separation of SBS, which mainly occurred after a 4-day storage. However, ΔSP48 after a 6-day storage met the specification requirements (i.e., below 2.5 °C). Thus, the attenuation degree of asphalt performance in field storage was not effectively characterized by ΔSP48 alone. Results from network strength (I) and SBS swelling degree tests revealed that the primary cause was SBS degradation and base asphalt aging. Moreover, conventional indexes, including penetration, ductility, and softening point, were used to build a prediction model for rheological properties after long-term storage using partial least squares regression model, which can effectively predict I, R, Jnr, G*/sinδ, and SBS amount. Correlation coefficient is above 0.8. G*/sinδ and I at the top and bottom storage locations had high coefficient with SBS amount. Thus, phase separation of SBSPMB should be evaluated during thermal storage.


2017 ◽  
Vol 744 ◽  
pp. 121-125 ◽  
Author(s):  
Mohd Ezree Abdullah ◽  
Nurul Najihah Mad Rosni ◽  
Ramadhansyah Putra Jaya ◽  
Haryati Yaacob ◽  
Norhidayah Abdul Hassan ◽  
...  

Environmental pollution caused by abundant wastes from agricultural activities has increased in recent years because of increased productivity. Agricultural waste recycling has been employed to solve this problem. Coconut shell charcoal (CSC) ash is a by-product of coconut shell (CS) used as a bitumen modifier to enhance the properties of the binder. This study investigated the effect of fineness charcoal ash from CS on the rheological properties of bitumen. Penetration, softening point, and viscosity tests were performed to determine the properties of the binder. Laboratory simulation of aging called rolling thin film oven test was applied in this study. CSC at different sizes (< 75μm, 75–150μm, and 150–300μm) was added to replace bitumen 60/70 PEN at 0%, 10%, 15%, and 20% by weight of the binder, respectively. Result showed that the bitumen became more viscous and that the softening point of bitumen increased, whereas the rate of penetration decreased when CSC was incorporated. CSC at a proper amount improved the resistance of bitumen to temperature susceptibility. In addition, the modification of bitumen can relieve the effect of aging. Modified bitumen shows better result when incorporated with the finest particle (< 75μm) of CSC compared with other sizes.


2015 ◽  
Vol 76 (9) ◽  
Author(s):  
E. Shaffie ◽  
J. Ahmad ◽  
A. K. Arshad ◽  
D. Kamarun

In this paper, the effects of nanopolyacrylate (NP) in binder modification on the empirical and rheological characteristics of the conventional binder were explored. The empirical and rheological binder properties were characterized using penetration, softening point, viscosity and dynamic shear rheometer (DSR) respectively.  These testings have become useful methods in characterizing of the binder performance on the pavement. The results indicated that NP polymer modification improved the physical properties of the conventional binder such as; penetration, softening point and temperature susceptibility. The results of viscosity test show that the NP polymer modified binder is more viscous than unmodified binder where viscosity increases with the increment of polymer content. The DSR results indicate that the NP polymer improves rheological properties of conventional binder, i.e. increasing the complex shear modulus (G∗) values and rutting parameters (G∗/sin δ), as well as decreasing the phase angle (δ) values. Therefore, it can be concluded that NP polymers considerably improves elastic properties and rutting resistance of binder and thus could be used for enhancing the asphalt pavement performance.


Author(s):  
Erkut Yalcın ◽  
Muhammed Ertuğrul Çeloğlu ◽  
Mustafa Akpolat ◽  
Özge Erdoğan Yamaç ◽  
Taner Alataş ◽  
...  

Styrene-butadiene-styrene (SBS) polymer is one of the most preferred additives to improve performance in hot mix asphalt pavements. The storage instability, in other words, the separation of a polymer-rich phase from the bitumen-rich phase in the course of storage and transportation is one of the prevalent problems in SBS modified bitumen. The present study attempted to obtain modified bitumen at the same performance level with the SBS modified bitumen, but stable with respect to the storage stability. For this purpose, both SBS and American Gilsonite (AG) were used in modified bitumen production. It was determined that modified bitumen at the same performance level was obtained with the use of 5 % SBS or 18 % AG in bitumen modification. It was also determined that the performance levels of the modified bitumen obtained with the use of 2 % SBS + 13 % AG, 3 % SBS + 10 % AG and 4 % SBS + 6 % AG were similar. Additionally, 2 %, 3 % and 4 % SBS modified bitumen were used for the assessment of storage stability properties of the SBS modified binders. These 8 different modified bitumen samples were tested for storage stability based on the EN 13399 standard. Penetration, softening point, rotational viscometer, bending beam rheometer, and dynamic shear rheometer tests were conducted on the samples. Based on all conducted tests, it was determined that more stable binders were obtained with the use of AG and SBS in terms of storage stability compared to solely SBS modified bitumen.


2016 ◽  
Vol 847 ◽  
pp. 413-417 ◽  
Author(s):  
Li Gao ◽  
Jian Ying Yu ◽  
Min Wu ◽  
Li Hui Xue

Ultraviolet (UV) absorber residue was used to modify bitumen. Effects of UV absorber residue on thermo-oxidative and UV aging properties of bitumen were evaluated by conventional physical properties and SARA (saturates, aromatics, resins and bitumenenes) analysis. The results showed that the viscosity aging index (VAI) and softening point increment (SPI) of bitumen decreased significantly due to introduction of the UV absorber residue, and the ductility retention rate (DRR) was evidently higher compared to the pristine bitumen. SARA show that UV absorber residue can effectively restrain the gelatinization of bitumen resulted from aging. As a consequence, the UV absorber residue modified bitumen displays enhanced aging resistance properties, which can be attributed to the physical sorption of activated carbon to lighter components in the thermo-oxidative aging process and the absorption of UV absorption residue to the ultraviolet light in the process of UV aging.


Author(s):  
Hussain U. Bahia ◽  
Huachun Zhai ◽  
Andres Rangel

In a recent survey of users and producers of modified asphalts, stability and short-term aging were two of the main concerns regarding the use of modified asphalts. In an NCHRP project, a concentrated effort was put into development of revised or new testing procedures to better characterize the nature of modified asphalt and to solve some of the difficulties with using existing aging procedures developed for neat asphalts and modified asphalts. Three main procedures have been proposed to complement the existing Superpave procedures: the laboratory asphalt stability test, for measuring the storage stability of asphalt binders; the particulate additive test, for separation of particulate additives; and the modified rolling thin film oven test for short-term aging. The background behind the development of these test methods is explained, and typical data collected for a number of modified asphalts are presented. The results indicate that these tests show high promise in covering characteristics not covered by the current Superpave binder specifications and in solving some of the problems with the existing aging methods. The results also indicate that the behavior of modified binder can be very complex and that the method of data interpretation is very critical.


2014 ◽  
Vol 599 ◽  
pp. 203-207
Author(s):  
Song Xu ◽  
Wei Dan ◽  
Wen Zu Li ◽  
Jian Ying Yu

Layered double hydroxides (LDHs)/SBS modified bitumens used for waterproofing membrane were prepared by melt blending using various contents of SBS and LDHs. Effects of the LDHs on physical properties and thermal oxidative aging performance of modified bitumen were investigated. The results show that softening point and low temperature flexibility of LDHs/SBS modified bitumen are increased simultaneously with the rise of SBS content, while they are little affected by the change of LDHs content. The thermal oxidative aging resistance of SBS modified bitumen is gradually improved with increasing LDHs content. In addition, the aging rate of SBS modified bitumen with LDHs are evidently lower than that without LDHs over time, which indicates that LDHs improve the ability of SBS modified bitumen to resist the thermal oxidative aging effectively.


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