Rut Damage And Experimental Research On Asphalt Pavement On Urban Roads In Changsha City

In recent years,with the increase of urban traffic and vehicle axle load,the deformation type damage of asphalt pavement is becoming more and more serious,especially in the intersection area and bus station due to the frequent starting and braking of various vehicles,resulting in asphalt pavement pushing package,rutting and other deformation type damage phenomena.For the serious problem of asphalt pavement deformation damage phenomenon,although China used the dynamic stability index obtained from the rutting test to verify the deformation resistance of pavement materials,but from the actual urban road　conditions,even if the use of asphalt mixture to meet the dynamic stability requirements,deformation damage problems are still endless,deformation damage problems are still endless.Therefore,for the current situation of deformation damage of asphalt pavement in Changsha area,especially from the perspective of materials to conduct an in-depth investigation and analysis of the deformation damage of urban asphalt pavement.In this paper,we investigate the deformation damage phenomenon of urban asphalt pavement in Changsha from the influencing factors affecting the deformation damage resistance of asphalt mixture,and drill core samples in typical sections for asphalt extraction test and sieving test to investigate the causes leading to the deformation damage of the road section;based on the Marshall test for asphalt mixture mix ratio design,through the comparative study of different rutting test methods,we not only investigate the deformation damage from We not only conducted a systematic comparison study of the two rutting test methods in terms of instrumentation,specimen forming method,test principle and method,but also used two rutting test methods to evaluate the performance of commonly used asphalt mixtures as test specimens.The occurrence of deformation and damage of the studied urban road section was investigated and analyzed,and it was found that the closer the distance from the bus stop area,the greater the rutting depth;the farther the distance from the bus stop area,the smaller the rutting depth;the closer the intersection area is to the parking line,the greater the rutting depth;the longer the red light time,the greater the rutting depth at the intersection location;the shorter the red light time,the smaller the rutting depth at the intersection location;the longer the red light time,the smaller the rutting depth at the intersection location.The longer the red light time,the greater the rutting depth at the intersection location;the shorter the red light time,the smaller the rutting depth at the intersection location;by measuring the gross bulk density of the core samples of different rutting depth sections,it was found that the compression density deformation was one of the causes of deformation and damage of the sections.Further sieve test and asphalt extraction test were conducted on the core samples of different rutting depths,and it was found that asphalt content and gradation have a great influence on the development of rutting,among which fine gradation is also an important cause of deformation and damage of urban asphalt pavement.Based on the asphalt mixture mix ratio design,the relationship between the rutting depth,the evaluation index of rutting test in China,and the rutting depth,the evaluation index of Hamburg rutting test,was established through the comparative study of different rutting test methods,and it was determined that the Hamburg rutting test method could be an effective supplement to the current testing methods.On the basis of the above work,four ideas for the improvement of the national standard rutting test method and suggestions for the use of Hamburg rutting test are proposed from the perspective of permanent deformation damage occurring in asphalt pavements.