Analysis and Evaluation of the Causes of Skid Resistance on the Asphalt Concrete

Factors affecting the skid resistance are devided into three categories: weather conditions, traffic fluctuations and parameters related to vehicle. One of the factors related to the pavement is the average depth of coarse texture. The main objective of this study is to obtain an average depth of pavement texture. In order to achieve this goal, an appropriate aggregation was selected from the Iran’s road pavement Regulations (open and continuous gradation 5). Some samples were made by Marshall Test using the selected gradation and six different types of pure bitumen 60-70 with the percentage of 4, 4.5, 5, 5.5, 6, 6.5% and calcareous mountain broken materials. After analyzing the results for each sample, the optimum bitumen percentage was obtained for each sample. Regarding the optimum bitumen, gyratory samples were made. The coarse texture effect on these samples was investigated through sand spread method (based on ASTM E965-96) and the most appropriate gradation was selected regarding the skid rtesistance. The results showed that an average depth of open coarse is better than continuous course. Also porous asphalt could be an appropriate option to eliminate the phenomenon of skid resistance due to possess suitable vacuum drainage and continuous transverse surface water.