Study On Unsaturated Asphalt Concrete Rainwater Infiltration Model

People have been studied on percolation models in many areas,no matter in theory or in practical applications. Many theoretical methods have been used to study on percolation models, such as the porous media theory method, renormalization group method, etc. Everything which related to the flow of liquid in engineering fields is needed to study to explore the security risks and destructive caused by seepage. Such as oil and gas field development, disaster prevention dam, slope stability and so on.Water damage of asphalt concrete pavement is the result of water and vehicle loads. Water in the asphalt concrete pavement involving seepage problems ,rainwater that infiltration into the asphalt concrete pavement lead to the water damage. This paper is based on asphalt concrete pavement water damage and rainwater infiltration. First ,introducing the theory of porous media into asphalt concrete pavement. Assuming Darcy's law applied to asphalt concrete seepage, therefore establishing saturated– unsaturated percolation model of asphalt concrete.Then under supports of the National Natural Science Foundation , developing permeameter that could accurately determine the permeability coefficient of asphalt concrete. Through measuring the permeability coefficient of large number of asphalt concrete specimens under different conditions to analysis various factors affect the permeability of asphalt concrete.Finally, useing the finite element software to simulate the infiltration of asphalt concrete pavement.This paper has analysised how rainwater distributes and move in each layer. Especially, this paper drawing the basic concepts of unsaturated soil mechanics to suppose that asphalt concrete pavement is in a non-saturated infiltration and drainage condition at the beginning of raining and after the rain stopped,that is the true state of the road . This paper focuses on this non-saturation of water infiltration and drainage of the road. People in foreign countries began to pay attention to this problem and study how such non-saturation affect water damage of asphalt concrete pavement. Because of more really reflects the state of water in road,it will provide a more realistic basis for lately further study on water damage of asphalt concrete pavement.This study was supported by the National Science Foundation (No.51078374) and Doctoral Fund of Ministry of Education (No.20095522110001).