Experimental Study On Road Performance Evaluation Of Asphalt Mixture Under Simulated Dynamic Water Pressure Test

Dynamic water pressure is one of the important factors to accelerate the early water damage of asphalt pavement.Since water accumulation on the road surface cannot be avoided,the influence of hydrodynamic pressure on the asphalt concrete pavement cannot be avoided,and such water damage will also develop to different breadths and depths over time.Water damage not only reduces the overall service level of the highway,but also greatly reduces its service life,and it also brings huge losses to the social economy.Therefore,it is of great theoretical and engineering significance to further study the influence of asphalt concrete pavement under the action of hydrodynamic pressure.In this study,with the help of the existing test system,the effect of simulated hydrodynamic pressure on the road performance of asphalt mixture is studied.The test system uses an air compressor,a vacuum extractor,and a maximum theoretical density tester as the main instruments to simulate the dynamic water pressure formed by the actual road surface.Taking AC-13 dense graded asphalt mixture as the research object,the changes of its mechanical properties under hydrodynamic pressure test conditions are studied,and the variation law of the asphalt mixture’s road performance is discussed..A large number of experimental research results show that:(1)The mass of suspended matter under the conditions of hydrodynamic pressure simulation test can effectively evaluate the anti-stripping performance of asphalt mixture,that is,when the quality of suspended matter is high,it shows the anti-stripping ability of asphalt mixture Poor;on the contrary,when the quality of suspended matter is low,it shows that the asphalt mixture has better anti-stripping ability.(2)Whether it is a loose mixture or a formed mixture test piece,after the action of dynamic water scouring,the rules of the test results are basically consistent: the high temperature stability,low temperature crack resistance,and water stability of the mixture As well as fatigue performance,it increases first and then decreases with the increase of the action time of water.(3)The hydrodynamic pressure before 4h will increase the overall mechanical strength of the asphalt mixture;after 4h,the hydrodynamic pressure has a weakening effect on the asphalt mixture and gradually increases,and the road performance and mechanical performance of the mixture decrease rapidly.