Relationship between surface material indices and skid resistance of concrete pavement

Traffic safety depends intensively on skid resistance (SR), which is primarily influenced by the texture of concrete pavement. Despite their importance, the role of fine aggregates in determining texture and SR remains unexplored. This study aimed to investigate this relationship by preparing 10 laboratory specimens with varying fine aggregate contents (high, low, and standard), partial (1 %, 5 %, and 10 %), and full replacements with hard sands (garnet and sandblast). The SR and texture were assessed using a dynamic friction tester and 3D laser profilometer after specific surface polishing intervals. A new SR prediction method was proposed using multiple linear regression analysis with surface material indices at specific wavelengths. The results revealed a strong correlation (0.922) between SR and the combination of micro- and macrotexture indices. Specimens with a higher fine aggregate content, and 5% and 10% replacement with garnet and sandblast respectively exhibited notable improvements in long-term SR. Evaluation of SR using the predicted indices indicated that the top 15% of the peak and bottom 15% of the valley materials on the texture at selected wavelengths enhanced friction and water drainage.