Numerical Analysis of Temperature Reduction Effect of Permeable Pavements

Abstract

Permeable pavements can effectively reduce the urban road surface temperatures. To study the cooling effect of holding water on the road surface under the comprehensive influence of the external water and heat environment, a numerical model established by a finite element analysis software and an indoor test were used to verify the temperature change behavior of the road surface under different heating temperatures and holding water conditions. The results show that the average error between the numerical model and indoor test is 3.5%, and the model reliability is high. Under the same conditions, the change in thickness of the permeable pavement surface and base course has a negligible effect on the temperature of the road surface. For every 100 J/(kg/°C) increase in the specific heat capacity of the upper surface course and lower surface course, the maximum daily road surface temperature can be reduced by approximately 2.1°C and 0.4°C, respectively. The road surface temperature shows a similar pattern when the thermal conductivity increases. Under dry conditions, the maximum daily road surface temperature can be reduced by approximately 3.4°C and 4.3°C for surface-permeable and fully permeable pavements, respectively. This study provides reference suggestions for optimizing the selection and design of urban road pavement structures from the perspectives of permeable pavement design, material parameters, and structure type.