The Influence of temperature to the performance of road subbase material produced from recycle asphalt pavement (RAP)

Abstract

This research investigates the effect of temperature on the performance of road subbase produced from recycled asphalt pavement (RAP). To prepare the RAP subbase, RAP was blended with low plasticity clay at 95%, 85%, 75% and 50% by dry weight. The optimum moisture contents of all mixtures were primarily determined based on the modified compaction test. Three groups of samples, with three replicates, were prepared by compacting the mixtures at optimum moisture content. Before the performance tests, two groups of samples were placed in the oven at 60 ºC and 150 ºC for 24 hours. Another group was left untouched at room temperature. Then, the California bearing ratio test, unconfined compressive strength test, and indirect tensile strength test were performed with the three groups of samples. The performance test results indicate that, without temperature effects, the strength of the RAP subbase is dependent on the compaction degree. On the other hand, with the increase in curing temperature, the strength of RAP subbase is highly influenced by the percentage of the RAP in the mixture not only the compaction degree. The results of this study concluded that a temperature of 60 °C resulted in a mixture of the RAP to the clay at a ratio of 75:25 and at a temperature of 150 °C at a mixture ratio of 75:25. CBR test the material will withstand a lot of strength.