Investigation on the performance of polymer-modified stone matrix asphalt for bus rapid transport pavement

Abstract

Abstract The application of the bus rapid transport (BRT) system has developed in many metropolitan cities owing to its cost-effective transportation which separates the bus routes from the private car route. However, the channelized bus load caused by narrow space operation in this road type leads to very fast pavement deterioration, especially, potholes and rutting issues have been a major concern in BRT pavement. Therefore, the main goal of this research is to develop a polymer-modified stone matrix asphalt (PSMA) with the aim of enhancing the permanent deformation resistance of pavement in this BRT section. PSMA mix designs were developed from different styrene-butadiene-styrene admixture contents and gradation types. Afterward, laboratory tests were conducted to evaluate the performance of the proposed mixture involving the dynamic modulus test and Hamburg wheel tracking test. The Falling Weight Deflectometer test was subsequently performed to verify the behavior of the best mixture in the severely damaged bus stop location in Seoul. The findings suggest that gradations impose a major impact on the performance of PSMA specimens, especially at high temperatures or low-frequency zone associated with congestion areas. In general, the test results confirmed the potential use of PSMA mixture to reinforce the bearing capacity of bus stop stations for sustainable infrastructure development.