Research On Asphalt Pavement Resist Permanent Deformation Under Persistent And Extreme High Temperature Conditions

With the global warming,the extreme high temperature weather phenomenon appears to happen more frequently in different places.Thus,asphalt pavement may show a serious of problems,like the rut,hug in high temperature conditions,because the poor temperature stability of asphalt.Nowadays,although a lot of researches have been done on the asphalt pavement proble,little research results have been reported at this point concerning the effect of extreme high temperature on rutting,since the extreme high temperature is not prominent in the past.The main purpose of this paper is to study the effect of the change of the internal temperature of asphalt pavement on the performance of asphalt pavement under the condition of continuous extreme high temperature.And,this paper used nanocomposite modified asphalt to alleviate the asphalt pavement in the continuous high temperature conditions.At the same time,the test road was pavement to verify the rationality of alleviating the asphalt pavement disease under continuous high temperature.Firstly,the internal temperature of asphalt pavement under continuous high temperature condition was studied by finite element simulation software-ANSYS Workbench.Temperature law of asphalt pavement structural layer obtained at different temperature(35?,38?,40?)by simulating the continuous 7 days of high temperature weather surface temperature field of asphalt pavement.Secondly,this paper studied permanent deformation of asphalt mixture under extreme high temperature conditions.The asphalt mixture damage model based on viscoelastic-plastic constitutive model was proposed by complex creep compliance.The method of determining the parameters of permanent deformation model of asphalt mixture considering damage was given.The asphalt mixture was subjected to three-axis repeated test and direct tensile fatigue test at 40?,60? and 67?.The permanent deformation model parameters of the asphalt mixture were considered according to the test results,and flow number formula were carried out at 60? and 67? temperature.Thirdly,with the development of nano-materials research and apply,this paper used nanomaterials as the modifier of asphalt to prepare nanocomposite modified asphalt.And the high temperature,low temperature,tensile property,fatigue,water stability and aging performance of the related nanocomposite modified asphalt mixture was carried out to obtain the composite modification according to the actual pavement function program.At the same time,in order to study the resistance to extreme high temperature performance of the existing asphalt mixture,the asphalt mixture were test with Hamburg rutting at different temperatures(including 60 ?,67 ? and 75 ?).The resulting to assess the type of asphalt mixture that was suitable for continuous extreme high temperatureresistance to rutting.Finally,the test road was carried out in this paper to test the final results of the relevant test plan.