水平-竖向荷载共同作用下水泥搅拌桩承载特性

Bearing Behavior of Cement-soil Pile under the Action of Both Horizontal and Vertical Loads

采用FLAC程序,研究了水平-竖向荷载共同作用下水泥搅拌桩的承载特性,获得了桩顶最大水平位移、桩身水平位移及桩顶沉降与不同荷载之间的关系。桩顶最大水平位移与水平、竖向荷载均呈正线性关系。竖向荷载对水平承载力有较大影响,破坏时的水平极限荷载随着竖向荷载的增加而减小。在桩体某一深度范围内出现了与水平荷载方向相反的水平位移,据此提出了第一零点和第二零点的概念。当水平荷载较小时,桩顶沉降与竖向荷载呈线性关系;当水平荷载较大时,随着竖向荷载的增加,桩顶沉降与竖向荷载呈非线性关系。随着水平位移的增大,桩体由中心受压转为偏心受压,加剧了桩身的不均匀沉降。

The bearing characteristics of cement-soil pile were analyzed under the action of both horizontal and vertical loads by FLAC software.The relationship between different loads and maximum horizontal displacement at pile-top,the horizontal displacement along the pile body,settlement at pile-top was obtained.The maximum horizontal displacement at pile-top has a positive linear correlation with the both horizontal load and vertical load.The horizontal ultimate load is decreased with the increasing of vertical load when the pile is broken.The direction of horizontal displacement around a deep range of pile is opposite of the direction of the horizontal load.The concept of the first zero point and the second zero point of the pile horizontal displacement is presented.The settlement at pile-top has a positive linear correlation with vertical load when the horizontal load is small;while the settlement at pile-top has a positive nonlinear correlation with vertical load when the horizontal load is high.Moreover,the differential settlement of pile is aggravated along with the increasing of horizontal displacement because the loading conditions are changed from concentric compression into eccentric compression.