成层地基中倾斜偏心荷载下基桩位移特性室内模型试验研究

A model test study on displacement of piles under inclined and eccentric loads in layered soils

为研究地面以上桩自由长度、桩身刚度、桩身微倾斜角度等因素对基桩位移特性的影响,以黏土模拟软弱土层,砂土模拟下卧持力层,自行设计自平衡装置施加倾斜偏心荷载,进行倾斜偏心荷载下两组6根木质柔性桩室内模型试验。试验结果表明,倾斜偏心荷载下基桩位移表现出明显的非线性,在受荷过程中,倾斜荷载、水平荷载、竖向荷载、地面处桩身水平位移、桩顶水平位移与桩顶转角均满足一定的规律。最后,提出了倾斜偏心荷载下基桩位移计算半经验公式,实测结果表明,理论计算结果与实测结果误差一般小于15%。

Model tests of 6 timber piles in two groups, with clay simulating upper soft soil and sand simulating bearing stratum, were conducted through a self-designed self-balancing apparatus for inclined and eccentric loading. The purpose of this study is to investigate the effects of free pile length above ground, pile stiffness and eccentricity on the displacement of piles. Analysis of the test results illustrates that the displacement of piles under inclined and eccentric loads is obviously nonlinear. A semi-empirical formula is presented for calculating the displacement of piles under both eccentric and inclined loads, with a relative error being under 15%.