饱和土中单桩受移动荷载作用的动力响应

Dynamic response of single pile embedded in saturated poroelastic half space subjected to moving loads

根据Biot动力理论,采用Fourier和Hankel变换方法得到了半空间饱和土受移动荷载及土体内受垂直简谐荷载作用下的变换域内基本解.再根据虚拟桩法,得出了移动载荷作用下桩基的第二类Fredholm积分方程.最后应用IFFT方法得到时间、空间域内单桩的动力响应.数值结果表明,移动荷载会引起桩身的负摩擦力;桩身最大轴力、孔压随移动荷载速度增加而增大;此外,在桩上端部会出现孔压集中现象.

Based on Biot＇ s theory, the general solutions to a poroelastic half space subjected to moving loads and the fundamental solution corresponding to a vertical harmonic force applied at the interior of a saturated half space are developed via the Fourier transform and Hankel transform. Utilizing Muki＇ method, the second kind of Fredholm integral equation describing the dynamic interaction between a pile and the half space is obtained. Numerical results in the time-space domain are obtained by performing the inverse Fourier transform. Numerical results show that the moving load can generate some negative frication for the pile. The maximum axial force of the pile and the pore pressure along the pile side increase with increasing velocity of the load.Also, the pore pressure concentration phenomena occur at the upper part of the pile.