The permeable asphalt pavements are rapidly developed and applied for the sponge city, but its bearing capacity for traffic load is insufficient. Aiming to solve this problem, a new kind of porous water retaining subbase was adopted to replace the traditional permeable subbase. Four typical coastal cities in South China were selected to analyze the rainfall pattern characteristics, and one of them was taken as an example for detailed discussion. According to the rainfall pattern characteristics in this region, the structure combination schemes of permeable asphalt pavement were put forward, and then the suitable pavement structure was systematically designed to satisfy the requirements of permeable capacity and bearing capacity. The results show that under the rainfall condition in this region, the minimum thickness of permeable subbase without surface runoff on the road surface should be 250mm, which is suitable for urban roads of medium traffic level with cumulative times of equivalent axle load of 10-12 million. The improved permeable asphalt pavement has both sufficient bearing capacity and good permeable function.
 

rainfall pattern characteristics, pervious road, design thickness, load carrying capacity