Performance study of porous asphalt mixture (PAM) for application in tropical environment
Tan, Daniel Chun Kiat
Date of Issue2015
School of Civil and Environmental Engineering
Centre for Infrastructure Systems
The study of the effects of tropical conditioning on the performance of porous asphalt mixtures was investigated in this project. The project was conducted in the context for the moisture conditions atypical to tropical countries such as Singapore. In particular the clogging, abrasion loss and indirect tensile performance tests were integrated with moisture conditioning measures, and their results used as key performance indicators of porous asphalt mixtures as determined in past researches. Four experimental mixes comprising a control gradation and three other test gradations with varying amounts of coarse aggregates were evaluated so as to investigate if any possible trends would be reflected across multiple gradations. Specimens were fabricated with the use of granite aggregates and PG76 bitumen. In the early stages of the project, the optimum binder content was determined for the entire course of the project. Overall experimental analyses showed a strong effect that moisture conditioning had on the key asphalt performance indicators. Specimens subjected to moisture conditioning across all four gradations showed severe decreases in their performance under clogging, abrasion loss and indirect tensile stress tests. Additionally, the degree to which moisture conditioning affects the performance of the porous asphalt mixture varied depending on the gradation of the porous asphalt mixture. The findings of this study indicate that future performance indicators of porous asphalt mixtures may consider the inclusion of tropical conditioning measures to determine the performance of the mixture and its suitability to be put to use in tropical regions. The project determines that with the severe impact moisture conditioning has upon present performance tests, its inclusion in the prevailing tests can aid in the development of better pavements that are stronger and more durable.
Final Year Project (FYP)
Nanyang Technological University