基于温度-车辆荷载作用下沥青路面细观力学响应

Micromechanical response of asphalt pavement under temperature-vehicle load

为了研究温度-车辆共同荷载作用下沥青路面各结构层细观力学响应,依据常用沥青路面各结构层材料级配及孔隙率建立了离散元模型,通过拟合室内单轴压缩应力-应变曲线获取模型的细观参数.在此基础上,对车辆荷载和不同温度作用下的沥青路面响应进行求解,分析各结构层细观力学响应及结构层颗粒变化情况.研究结果表明:在移动荷载及温度共同作用下,随着路面结构层深度增加,垂向位移逐渐降低,温度越高垂向位移越大;各结构层垂向应力随路面深度增加而依次减小;水平方向各结构层应力情况复杂,上面层处于受压状态,其余结构层颗粒既有受压也有受拉状态;切向应力处于拉应力与压应力交替状态,温度对颗粒应力影响较大;颗粒前期速度振动较为剧烈,后期速度振动较为平缓.

In order to study the micromechanical response of each structural layer in asphalt pavement under temperature-vehicle load, a discrete element model is established based on the material gradation and porosity of each structural layers of common asphalt pavement. The mesoscopic parameters of the model are obtained by fitting the indoor uniaxial compression stress-strain curve. On this basis, the response of asphalt pavement under vehicle load and different temperatures is obtained, and the microscopic mechanical response and particle changes of each structural layer are analyzed. The research results show: under the combined action of moving load and temperature,as the depth of the pavement structure increases,the vertical displacement gradually decreases, and the higher the temperature, the longer the vertical displacement;the vertical stress of each structural layer decreases with the increasing pavement depth;the horizontal stress of each structural layer is complex, as the upper layer is compressed, and the particles in the remaining structural layers are in mixed states of compression and tension;the tangential stress alternate from tensile stress to compressed stress, and temperature has a great impact on particle stress;the velocity vibration is more severe in the early stage of the particle, while the vibration weakens in the later stage.