利用有限元方法模拟现场倾斜荷载试验及现场负摩阻试验,并对倾斜荷载与负摩阻共同作用下的基桩受力特性进行分析。首先,施加竖向荷载;然后,分先后顺序施加水平荷载与产生负摩阻的地面荷载。研究结果表明:地面荷载先于水平荷载施加对基桩承载有利,当地面荷载为竖向荷载的1.3%时,承受倾斜荷载时基桩桩顶水平位移、桩身最大弯矩、桩身最大轴力与未施加地面荷载情况相比,分别减小35.1%,22.2%和5.6%;当地面荷载后于水平荷载施加时,基桩的水平承载特性与仅受水平荷载时的相比无明显区别;桩侧负摩阻力略增大。
Field test under inclined load or negative skin friction (generated by the ground load) was simulated using finite element method, and the bearing features under both inclined load and negative skin friction were stimulated. Firstly, the axial load was applied, then the horizontal load and ground load were applied according to the order. The results show that applying ground load prior to the horizontal load is beneficial to the pile, when the ground load is 1.3% of the axial load, the horizontal displacement, maximum bending moment and maximum axial forces of the pile under inclined load are reduced by 35.1%, 22.2% and 5.6% respectively compared with that without ground load. The ground load applied after horizontal load has no obvious difference to the horizontal bearing feature, but the negative skin friction increases slightly.