Calculation Method For Permanent Deformation Of Asphalt Pavement On The Basis Of Roughness

Pavement roughness is one of the crucial indexes for the assessment of itsconstruction and performance. When the roughness is deteriorated below some criticallimit by years of use, the pavement, far from being standard, is required to be revampedor reconstructed. On the grounds of statistics on roughness measurement ofK1589~K1593section of Jieshi-Shuijiang highway, combined with a sequence of tests,theoretical analysis and model simulation of asphalt mixture repeated load permanentdeformation, this thesis is on the calculation of the permanent deformation of asphaltpavement varying with axle load and temperature ranges, on the prediction of itsroughness worsened by years and on the estimation of its remaining life, which all aretaken in consideration as the reference for proper maintenance program①The sine-wave-shaped pavement model that stimulates the actual roughness isestablished under the guidance of the M.W.Sayers theory and measured results.②According to the research on asphalt pavement temperature in Chongqing, thetemperature, mainly which of2cm below pavement, is collected and counted into aclean picture of pavement frequency and downward distribution of temperature range.③Viscoelasticity model that is suitable for permanent deformation of asphaltmixture under repeated load is systematically reasoned based on the modified Burgersmodel. With the assistance of1stOpt, extremely precise parameter of mechanical modelis figured up, on the basis of the outcome of triaxial repeated load permanentdeformation test on asphalt mixture---SMA-13, AC-20, ATB-30---affected by thedeviator stress and temperature. Three-dimensional surface of cycles-partial stress-strain" under different temperatures is obtained by Origin8.0, thus predicting thepermanent deformation pattern from tests in the midst of lack of statistics④Under the principle of superposition, the model of permanent deformation ofasphalt pavement is proposed, which takes into consideration such factors as axle loads,temperature ranges, material properties and load times. Taking K1589~K1593section ofJieshi-Shuijiang highway as example, partial stress on pavement under differenttemperature ranges and axle loads is counted. Given material properties of asphaltmixture in various triaxial repeated load tests, the numbers of standard axle loads underrepresentative temperature ranges and in different axle loads are analyzed, and finallythe model is established whose capability of predicting roughness of asphalt pavement of Jieshi-Shuijiang highway and estimating its remaining life, all making contributionsto scientifically grounds and references for pavement management and maintenance.