饱和半空间层状土体中群桩动力响应分析(英文)

Dynamic responses of pile groups embedded in a layered poroelastic saturated half-space to harmonic axial loads

主要研究了轴向荷载作用下层状饱和土体中群桩的动力响应问题.基于Biot理论,利用传递、透射矩阵法(TRM)推导了竖向圆形荷载作用下层状饱和土体的频域基本解,再根据Muki方法,利用第二类积分方程构建了层状半空间与群桩相互作用的动力积分方程.通过与已知文献结果比较,验证了本方法的正确性.计算结果表明,在两层土中,桩间距较小的群桩,上部软土层的厚度对中心桩和边桩的差异较大,而对于疏桩,影响不大;对于三层饱和土体,中间夹层越硬,群桩的阻抗越大,反之,群桩的抗力越小.

The dynamic response of a pile group embedded in a layered poroelastic half space subjected to axial harmonic loads is investigated in this paper. Based on Blot＇ s theory, the frequency domain fundamental solution for a vertical circular patch load applied in the layered poroelastic half space is derived via the transmission and reflection matrices （TRM） meth- od. Utilizing Muki＇ s method,the second kind of Fredholm integral equations describing the dynamic interaction between the layered half space and the pile group is constructed. The proposed methodology was validated by comparing results of this pa- per with a known result. Numerical results show that in a two-layered half space, for the closely populated pile group with rigid cap, the upper softer layer thickness has considerably different influence on the center pile and the comer piles, while for sparsely populated pile group, it has almost the same influence on all the piles. For a three-layer half space, the presence of a stiffer middle layer in the layered half space will enhance the impedance of the pile group significantly, while a softer middle layer will reduce the impedance of the pile group.