饱和土中刚性排桩对平面SV波的隔离分析

Analysis of vibration isolation of a row of rigid piles to plane SV waves in saturated soil

在Biot波动理论的基础上,用单排刚性排桩作为屏障,对全空间饱和土中入射平面SV波进行了隔离分析。采用波函数展开法,将散射波的势函数展开成Fourier-Bessel级数的形式,利用一组可以求解多散射问题的圆柱坐标系统和桩土界面处位移连续的条件,以及刚性桩的动力平衡条件,得到问题的理论解。对影响排桩隔离效果的桩间距和饱和土的渗透系数等参数进行了分析,结果表明,桩间距对饱和土中排桩的隔离效果有较明显影响;与弹性土体中排桩的隔离效果相比,饱和土中排桩的隔离效果有所不同,随着饱和土渗透系数的减小,排桩的隔离效果越好。

On the basis of Biot＇s dynamic theory, a row of rigid piles is used as a barrier for SV waves in homogeneous unbounded saturated soil. Based on wave function expansion method, the potential functions of scattered waves are expanded into Fourier-Bessel series; and a set of cylindrical coordinate systems is utilized in such a way that it allows to solve the problem of multiple scattering; the solution is determined by imposing continuity and equilibrium conditions at the soil-pile interfaces. A parametric analysis is conducted to study the influence of the pile spacing and soil permeability on the isolation effect. The results show that the pile spacing has a significant influence on isolation effect in saturated soil. Comparing the isolation effect in elastic soil there is a different isolation effect for SV waves in saturated soil. As the permeability coefficient of saturated soil decreases, the isolation effect of a row of rigid piles is improved.