Asphalt Treated Permeable Layer Design And Pilot Study

According to a lot of investigations on pavement service condition, inadequate subsurface drainage of pavement has been identified as a primary cause of unsatisfactory pavement performance and premature failures. It is commonly recognized that subsurface drainage system can improve pavement performance and extend service life.As an essential part of subsurface drainage system, the layer setting and characteristics of asphalt treated permeable material directly affect the performance of subsurface drainage system, which is lucubrated in this paper.Based on the typical semi-rigid pavement without permeable layer, using multilayer elastic system program, rational pavement structure with permeable layer at different locations is first analyzed. Then, using statistical method, performance indexes are compared, and the prior layer setting is obtained.Through elaborate indoor tests, the drainage performance, mechanics performance and durability of asphalt treated permeable material are researched. By statistical analyses of vast test data, the balance range of air voids is obtained, via performance tests in different saturation conditions, the durability of the material is gained.Finally, this paper brings forward the mix integrated design method of asphalt treated permeable material incorporating the results of structure analyses and tests. And the rational proposal and requirement for pavement subsurface drainage system of test road is suggested.