MECHANICAL MODELING AND INVESTIGATION OF PAVEMENT SLIPPERINESS DURING OR AFTER RAIN

Pavements during or after rain are prone to become considerably slippery for pedestrians and motor vehicles. This natural phenomenon is investigated by using the Terzaghi's consolidation model, the shear strength theory and the effective stress principle, within the scope of soil mechanics. A methodology for assessing the slippery pavement is established on the assumption of a simplified 1D equivalent model. A safety factor against sliding along the pavement surface is proposed in terms of the shear strength of the consolidating soil divided by its shear stress. Based on the engineering empirical parameters of common soils, a case study of pedestrians on the sidewalk is statistically conducted to qualitatively and quantitatively reveal the control factors of the pavement slipperiness. It is shown that the evaluated safety factor against sliding for the sandy pavement is approximately 6.0 to 9.0 times greater than that for the clayey pavement. The soil mechanics-based modeling is a promising novel approach to the slip resistant or anti-skid pavement design and evaluation.