抗滑桩受荷段前侧有限范围地层的地基抗力系数取值方法

Evaluation method for elastic foundation coefficient of finite downslope soil against loading segment of stabilizing piles

为确定在抗滑桩受荷段前侧有限范围土体条件下地基抗力系数的取值方法,基于抗滑桩计算的侧向受荷弹性地基梁法,并结合塑性极限分析上限法,考虑全桩内力与变形连续性,且以受荷段前侧土体无限情况下的地基抗力系数的比例系数值为基准,分析推导出抗滑桩受荷段前侧有限范围土体条件下该比例系数的取值方法,得到了地基抗力系数的比例系数与受荷段前侧土体坡度之间的关系,通过数值模拟进一步验证了所提方法的合理性。针对不同土体物理力学参数和抗滑桩参数条件下的案例分析结果表明,地基抗力系数的比例系数随受荷段前侧土体坡度增加呈非线性减小,抗滑桩嵌固段深度、截面尺寸、受荷段前侧土体黏聚力、内摩擦角和重度对桩前土体的该比例系数均有影响,但土体重度影响并不明显,而其他因素影响则呈较显著的正相关性影响。

In order to determine the evaluation method of lateral elastic foundation coefficient of the finite soil mass against the loading pile segment,based on the proportion coefficient of the foundation coefficient of the corresponding infinite soil mass,the laterally loaded beam-on-elastic-foundation method for a stabilizing pile is adopted in combination with the upper bound limit analysis method under the consideration of the internal forces and deformation continuity of the whole pile element.Thus,a calculation method for the proportion coefficient of the lateral elastic foundation coefficient of the finite soil mass is provided.The relationship between the proportion coefficient with the slope angle of the finite soil mass is determined.The proposed method is verified by numerical simulation method for a practical example.In the case of various physical and mechanical parameters of soil mass and stabilizing pile,analysis results of the example show further that the proportion coefficient decreases nonlinearly with the increase in the slope angle of the local soil.Also,the length of embedded segment(below the slip surface)and the size of cross section of stabilizing piles,cohesion,internal friction angle,and unit weight of the local soil have effects on the proportion coefficient.But the influence of the unit weight is minor,other factors have significant positive correlations with the proportion coefficient.