矩形壁板桩群桩竖直承载特性的理论分析

Theoretical analysis of vertical load-carrying behavior of rectangular barrette groups

矩形壁板桩不具有圆形桩的轴对称性,因此壁板桩群桩的承载特性及群桩效应不仅受桩间距的影响,而且受桩身截面形状以及群桩布置方式的影响。为分析这些因素,利用Mindlin方程和静力平衡条件建立了求解有无刚性承台时壁板桩群桩的荷载沉降计算方法。分析结果表明,在设计群桩时壁板桩应尽可能沿其纵向布置(即沿壁板桩的长边方向布置);对于具有常规截面尺寸的壁板桩,桩的对边距应超过2m,以减小群桩效应。

Unlike a circular pile, the cross section of a rectangular barrette is nonaxisymmetrical. Therefore, not only the pile spacing but also the pile shape and the pile group layout will have influence on both the load-carrying behavior and the pile group effect of barrette groups. In order to analyze these influencing factors, a calculation method is proposed for obtaining the load-settlement relationship of the barrette groups with or without a rigid cap, using the Mindlin equation and the static force equilibrium equation. It has been found that, when designing a barrette group, barrettes should be aligned longitudinally (i.e., along their longer sides); and for attenuating the pile group effect of the barrettes of typical size, the face-to-face spacing among barrettes should be greater than 2 m.