Evaluation of the Effects of Engineered Crumb Rubber (ECR) on Asphalt Mixture Characteristics

2021 ◽  
Vol 50 (2) ◽  
pp. 20210077
Author(s):  
Punyaslok Rath ◽  
J. Meister ◽  
B. Jahangiri ◽  
W. Buttlar
Keyword(s):  
2021 ◽  
Vol 13 (15) ◽  
pp. 8172
Author(s):  
Kechen Wang ◽  
Xiangyu Chu ◽  
Jiao Lin ◽  
Qilin Yang ◽  
Zepeng Fan ◽  
...  

Tire—pavement interaction behaviours result in large amounts of wearing waste matter, which attaches to the surface of the pavement and is directly exposed to the surrounding environment. This kind of matter imposes a great challenge to the environment of the road area. The current study is devoted to carrying out a comprehensive investigation of the formation mechanism of tire—pavement wearing waste (TPWW), as well as the resulting environmental risks. A self-developed piece of accelerated polishing equipment, the Harbin advanced polishing machine (HAPM), was employed to simulate the wearing process between vehicle tires and pavement surfaces, and the TPWW was collected to conduct morphological, physical, and chemical characterisations. The results from this study show that the production rate of TPWW decreases with the increase in polishing duration, and the coarse particles (diameters greater than 0.425 mm) account for most of the TPWW obtained. The fine fraction (diameter smaller than 0.425 mm) of the TPWW comprises variously sized and irregularly shaped rubber particles from the tire, as well as uniformly sized and angular fine aggregates. The environmental analysis results show that volatile alkanes (C9–C16) are the major organic contaminants in TPWW. The Open-Graded Friction Course (OGFC) asphalt mixture containing crumb rubber as a modifier showed the highest risk of heavy metal pollution, and special concern must be given to tire materials for the purpose of improving the environmental conditions of road areas. The use of polyurethane as a binder material in the production of pavement mixtures has an environmental benefit in terms of pollution from both organic contaminants and heavy metals.


CivilEng ◽  
2021 ◽  
Vol 2 (2) ◽  
pp. 370-384
Author(s):  
Hossein Noorvand ◽  
Kamil Kaloush ◽  
Jose Medina ◽  
Shane Underwood

Asphalt aging is one of the main factors causing asphalt pavements deterioration. Previous studies reported on some aging benefits of asphalt rubber mixtures through laboratory evaluation. A field observation of various pavement sections of crumb rubber modified asphalt friction courses (ARFC) in the Phoenix, Arizona area indicated an interesting pattern of transverse/reflective cracking. These ARFC courses were placed several years ago on existing jointed plain concrete pavements for highway noise mitigation. Over the years, the shoulders had very noticeable and extensive cracking over the joints; however, the driving lanes of the pavement showed less cracking formation in severity and extent. The issue with this phenomenon is that widely adopted theories that stem from continuum mechanics of materials and layered mechanics of pavement systems cannot directly explain this phenomenon. One hypothesis could be that traffic loads continually manipulate the pavement over time, which causes some maltenes (oils and resins) compounds absorbed in the crumb rubber particles to migrate out leading to rejuvenation of the mastic in the asphalt mixture. To investigate the validity of such a hypothesis, an experimental laboratory testing was undertaken to condition samples with and without dynamic loads at high temperatures. This was followed by creep compliance and indirect tensile strength testing. The results showed the higher creep for samples aged with dynamic loading compared to those aged without loading. Higher creep compliance was attributed to higher flexibility of samples due to the rejuvenation of the maltenes. This was also supported by the higher fracture energy results obtained for samples conditioned with dynamic loading from indirect tensile strength testing.


Author(s):  
Lily D. Poulikakos ◽  
William Buttlar ◽  
Nicolas Schüwer ◽  
Davide Lo Presti ◽  
Tobias Balmer ◽  
...  

2021 ◽  
Vol 54 (5) ◽  
Author(s):  
M. Bueno ◽  
R. Haag ◽  
N. Heeb ◽  
P. Mikhailenko ◽  
L. Boesiger ◽  
...  

AbstractIncorporating crumb rubber (CR) using the dry process, directly in the asphalt mixture rather than into the bituminous binder requires no plant retrofitting, and therefore is the most practical industrial method for CR incorporation into asphalt mixtures. Nevertheless, very few large scale studies have been conducted. This work uses a holistic approach and reports on the functional and environmental performance of asphalt mixtures with different concentrations of CR fabricated employing the dry process in asphalt plants. Gaseous emissions were monitored during the production and laboratory leaching tests simulating the release of pollutants during rain, was conducted to evaluate the toxicology of both the CR material alone and the modified asphalt mixtures. In addition, laboratory compacted samples were tested to assess their fatigue behavior. Furthermore, noise relevant surface properties of large roller compacted slabs were evaluated before and after being subjected to a load simulator (MMLS3) to evaluate their resistance to permanent deformation. The results confirm that comparable performance can be achieved with the incorporation of CR using the dry process for high performance surfaces such as semi-dense asphalt, which usually require the use of polymer modified binders. Environmental performance improvement can be achieved by a washing step of the CR material that could remove polar CR additives which have commonly been used as vulcanization accelerator during rubber production.


2012 ◽  
Vol 193-194 ◽  
pp. 452-457 ◽  
Author(s):  
Meng Yun Huang ◽  
Jing Hui Liu ◽  
Xi Zhang ◽  
Dan Ni Li

Using the waste crumb rubber modified asphalt to pave the road surface could reduce cost and save energy. However,in order to obtain adequate workability, the mixing temperature and compaction temperature of rubberized asphalt binder and its mixture is much higher than those of conventional asphalt mixtures. Warm Mix Asphalt (WMA) is the name given to certain technologies that reduce the production and placement temperatures of asphalt mixes. One of the main benefits advertised is the increased workability at conventional and lower compaction temperatures with the WMA addition. This paper evaluates whether there are any synergy effects of using warm mix technologies and Asphalt Rubber(AR) hot mixes. This paper summarizes a lab research to evaluate the workability of Asphalt Rubber hot mixes containing warm mix technologies. Both asphalt binder and asphalt mixture were evaluated and compared. The research suggests that combining WMA technology with Asphalt Rubber mixtures is a win-win.


2018 ◽  
Vol 20 (6) ◽  
pp. 1413-1428 ◽  
Author(s):  
Jizhe Zhang ◽  
Zhanyong Yao ◽  
Tenghai Yu ◽  
Shengjie Liu ◽  
Hongguang Jiang

2010 ◽  
Vol 168-170 ◽  
pp. 1145-1148 ◽  
Author(s):  
Xin Qiu ◽  
Lan Yun Chen ◽  
Liang Xue

The paper investigates the effects of different concentrations of crumb rubber (CR) on the pavement performance of the conventional penetration-grade 80/100 bitumen and the dense-graded wearing course asphalt mixture (AC16). A wet process and 0.6mm size CR were used and the control variables included three types of CR of concentrations 5%,10% and 15% by total weight of binder. The evaluations were twofold. Firstly, a comparison of the basic and rheological properties of those modified and unmodified binders was conducted. Secondly, a comparison of the resistance to moisture damage, low temperature cracking and permanent deformation of the AC16 and CR modified AC16 was performed. The results show that all the CR modified binders and mixtures are found to have improved performance as evaluated by a series of laboratory tests. In addition, among three CR concentrations, AC16 modified with 10%CR by total weight of binder exhibits the most satisfactory performance properties with respect to the resistance to moisture damage, permanent deformation and low temperature cracking.


2013 ◽  
Vol 368-370 ◽  
pp. 933-938 ◽  
Author(s):  
Qi Ying Niu ◽  
Jun Yong Zhao ◽  
Ru Kai Li

Through a series of mechanical properties experiment of recycled asphalt mixture composed of waste asphalt mixture 20% and different content of rubber powder, the paper analyzes and compares the elasticity, tensile strength and bending strength of asphalt mixture and recycled asphalt mixture, concluding that recycled asphalt mixture that mixed with crumb rubber content of 20% can completely replace the new asphalt mixture in the application. It has great significance for the future to recycling waste asphalt mixture in the highway.


Sign in / Sign up

Export Citation Format

Share Document