Evaluation Of Drainage Performance And Determination Of Maintenance Time Of Porous Asphalt Pavement During Operation Period

With the popularity of sponge city and the improvement of the demand on road surface function,porous asphalt pavement has been rapidly applied and developed in domestic road construction.Due to its large voids,porous asphalt pavement has excellent drainage performance,which can effectively improve traffic safety in rainy days,and also has environmental features such as noise reduction and cooling etc.However,engineering application experience shows that,during operation period,due to the impact of load and plug on the pavement void structure,the functional characteristics of porous asphalt pavement has a serious attenuation with the opening time.Drainage function is an important function of porous pavement,and it is of great engineering significance to study the drainage function of porous asphalt pavement in operation period.On the basis of summarizing the existing testing methods of drainage performance of porous asphalt pavement,the testing method of indoor and outdoor seepage performance of this paper was determined.A testing device capable of simulating the actual rainfall was made indoor to test the drainage capacity of porous asphalt mixture.The seepage test method was used to test the indoor and outdoor drainage performance.Through rutting test,clogging simulation test and seepage test,the attenuation characteristics of drainage function of porous asphalt pavement under the action of load and plugging were studied,and the relationship between the permeability coefficient and the connected porosity of porous asphalt pavement in the process of plugging was established.Based on the analysis of runoff mechanism of the actual pavement,the relationship among the allowable limit rainfall intensity,the coefficient of seepage and the connected porosity was established through the simulated rainfall test and seepage test.The minimum connected porosity and permeability coefficient of porous asphalt pavement with different pavement parameters to adapt to different rainfall intensity were obtained,and the maintenance time of porous asphalt pavement was put forward.The relationship between the connected porosity and the water recession time of the pavement was established through simulated water recession test.On the basis of summarizing the functional maintenance methods and cleaning equipment of porous asphalt pavement at home and abroad,the drainage function recovery vehicle was selected to clean the pavement of the support project.According to the test results of the seepage coefficient of the pavement on site and later,the evaluation and analysis of the seepage performance and recovery effect of the support project pavement were carried out,and suggestions on the maintenance of the drainage function of the porous asphalt pavement were put forward.