Characteristics of subsurface flow in porous pavement
HOU Li-Zhu, LIU Jiang-Tao, LV Jian-Hua
1.School of Water Resources and Environment, China University of Geosciences, 100083, Beijing,China;
2.Key Laboratory of Water Resources and Environmental Engineering of Beijing,China University of Geosciences, 100083,Beijing,China
Abstract：Impervious surfaces have since a long time been held responsible for the destruction of watershed integrity in urban and urbanizing areas as cites are being covered by airtight concrete surfaces like roads and buildings. In order to improve surface infiltration capacity, it is necessary to transform hardened grounds like sidewalks, bicycle tracks, leisure squares and courtyards to porous pavements. For studying the runoff characteristics of porous pavements, a series of simulated rainfall experiments under different rainfall intensities (31.38,42.32,50.60,58.88,69.82, and 78.09 mm/h) were conducted. The runoff generation process and the percentages of the subsurface runoff as part of the total precipitation are discussed in this paper. The results show that subsurface flow is the dominant runoff generation process. The percentages of the subsurface runoff vary with different rainfall intensities. Under the same pavement type, the ratio of the subsurface runoff to the total precipitation increases with an increase in the rainfall intensity. The infiltration capacity of the underlying surface of a city will be improved by increasing the proportion of permeable bricks and porous concrete block with a lower sand proportion.
2014, Vol. 12 
