行车速度对沥青路面力学参数及响应的影响

Effects of Vehicle Speed on Mechanical Properties of Asphalt Mixtures and Pavement Responses

利用室内试验确定的沥青混合料的动态模量主曲线和时间-温度转化因子,结合实测的冬天和夏天沥青路面结构的典型温度场,定量分析了行车速度对沥青路面材料性能及结构力学响应的影响.结果表明,当行车速度从10 km/h增加到130 km/h时,路面结构内动态模量可增加3倍以上,路表弯沉、沥青层底拉应变和土基顶面压应变等关键力学响应可减少20%以上.在冬天和夏天,材料性质及路面响应随车速的变化幅度有所不同.研究表明,为了得到更客观的结果,在路面结构分析和设计中应考虑行车速度的影响.

Effects of vehicle speed on material properties of asphalt pavement and structure responses are analyzed quantitatively using dynamic modulus master curves and time-temperature shift factors of asphalt mixtures are obtained from laboratory tests, along with pavement temperature data measured in the field. The results indicate that when vehicle speed increases from 10 km/h to 130 km/h, dynamic modulus in the pavement could increase by 12 times, and critical pavement responses such as surface deflection, tension strain at the bottom of asphalt layer, and compressive strain at the top of subgrade could increase by more than 20%. The increasing magnitudes of the material properties and pavement responses are different in winter and summer. This study suggests that vehicle speed should be taken into consideration in asphalt pavement analysis and design.