不平顺路面对交通荷载引起的地基振动影响

为研究不平顺路面对交通荷载引起的成层地基振动的影响，建立交通荷载-不平顺路面-双层地基耦合模型，分别采用单相弹性介质理论与Biot饱和两相介质理论模拟地基上、下层土体，采用Kirchhoff薄板理论模拟路面系统，采用正弦曲线模拟不平顺路面；通过线性Hertzian接触模型得到不平顺路面引发的车轮-路面动力荷载. 采用Fourier变换求解系统控制方程，通过快速Fourier逆变换（IFFT）求得时域结果. 数值研究结果表明，不平顺路面引发的车轮-路面动力荷载对成层地基振动响应的影响不容忽视. 当上层土体模量较小时，动力荷载引起的地表加速度大于轴重荷载引起的加速度，是引起地表振动响应的主要因素；随着上层土体模量增大，动力荷载引起的振动相对减小，但仍不可忽略. 此外，动力荷载是引起下卧饱和土地基超静孔压响应的主要因素.

Influences of pavement irregularity on ground vibrations generated by moving traffic load

A traffic load-uneven pavement-double-layered ground coupling model was established in order to study the influences of pavement irregularity on the vibrations of layered ground generated by moving traffic load. The upper and lower soil layers were simulated as elastic medium and a fully saturated poroelastic half-space governed by Biot’s theory, respectively. The pavement was simplified as a Kirchhoff thin plate, and the road surface irregularities were simulated by sine curves. The wheel-road dynamic loading was obtained through the linear Hertizian contact model. The governing equations of this coupling model were solved by the Fourier transform and the time-domain results were obtained by applying the inverse fast Fourier transform (IFFT). Numerical results show that the influence of wheel-pavement dynamic loading caused by pavement irregularity on the vibration of layered foundations cannot be ignored. When the shear modulus of the upper soil was small, the acceleration of the ground surface caused by the dynamic loading was greater than that caused by the axle load, which is the main factor that causes the ground surface vibration response. As the shear modulus of the upper soil layer increased, the vibration caused by the dynamic loading decreased, but it is still non-negligible. In addition, the dynamic loading is the main factor that causes the excess pore water pressure response in the lower saturated soil layer.