不同土体中单排弹性桩对水平向剪切波的隔离

The isolation of horizontal shear wave using single row of elastic cylindrical piles in bi-medium soils

采用Green函数法和"契合"思想研究不同土体中界面上单排弹性桩对SH波的隔离问题。首先构造适于本问题的位移Green函数,然后利用"契合"思想并结合界面上的应力和位移连续条件,将问题转化为一组第一类Fredholm积分方程,得到了弹性桩后位移和透射系数的解析表达式,并进行数值求解。最后作为算例,给出了等间距单排8个弹性圆柱桩对SH波的隔离效果图,分析了剪切弹性模量、桩间距等对桩后隔离效果的影响规律。通过分析曲线得出:隔振的最佳区域并不是弹性桩中心线后的近距离范围内,而是位于弹性桩后的一定距离上;当桩间距s/R<1时,桩后区域取得最佳隔振效果。

Based on the methods of Green＇ s function and conjunction, the isolation of horizontal shear wave using single row of elastic discontinuous barrier in hi-medium soils is studied. The displacement Green＇ s function, which is suitable for the present problem is constructed by using complex variable function. Based on the method of con- junction and the continuity condition of the interface, the problem is reduced to a series of Fredholm integral equa- tions of the first kind. The analytical expressions of displacement and transmission coefficient behind the elastic bar- rier are established, which are solved by numerical method. Some calculation examples, which are assumed that there are eight elastic cylindrical piles with equal space are plotted to discuss the influences of the shear elastic modulus, the pile spacing etc. on the isolation effect. It concludes by analyzing these curves that the best isolation location is in a distance behind the elastic piles and isn＇ t in the close range of the center line ; The best isolation effect is obtained when the pile spacing is s/R 〈 1.