Study On Asphalt Mixture Ruttng Resistance And Evaluation Index In Long-steep Longitudinal Gradient

The rut of asphalt pavement has become the main failure modes of the asphalt pavement,particularly serious in the steep and long slope sections. The rut greatly affected pavement lifeand traffic safety. Therefore，studying the formation mechanism and control measures of rut inlong and steep slope sections of asphalt Pavement is not only necessary，but also urgent.Firstly, analyzing the reason of damage of asphalt pavement in steep and long slopesections. Studies have shown that the main reasons which cause the rut of steep and long slopesections is:①Driving speed will slow down when climbing, which make rut easier to produce;②With the vehicle load prolonged duration of action on the road, Equivalent to indirectlyincrease the instantaneous temperature of the road, so the rut more likely to occur.③The longand steep slope sections of asphalt pavement affected a horizontal force is bigger than ordinarypavement. Compared with the ordinary pavement is also more likely to destruction.④The largervehicle load, the steeper of the road, The speed of the car will be reduced faster, The smaller thespeed when reach a stable speed, Combination of time-temperature equivalence principle, theasphalt pavement will be damaged more serious.Secondly, through the indoor experiments to study the steep and long slope sections asphaltpavement material. Studies have shown that SBS modified asphalt rut resistance superior toordinary road asphalt. Through the mix design of SMA and AC class asphalt mixture, resultshow that SMA class asphalt mixture rut resistance superior to AC class asphalt mixture. On thisbasis, through rutting test on different aggregate gradation, which showing that the skeleton densestructure rutting resistance performance of the best.In order better to reflect the characteristics of the asphalt mixture, this article will use acombination of theoretical and experimental. This work get creep curve from axis static loadcreep test, and discuss visco-elastic behavior of asphalt mixture. Using Burgers constitutivemodel as the based constitutive model to study asphalt mixture performance indicators. Throughstudy the creep test，using non-linear least squares method to analysis of the test results todetermine Burgers constitutive model material parameters.Finally，through creep test data to calculate the Burgers model parameters. Analyze therelationship between the Burgers model parameters and main indicators of ruts experimental. Toexplore the index that can be used to evaluate the rutting.