轴向荷载对横向受荷桩承载性状影响的参数分析

基于小变形假定,建立受轴向荷载作用的横向受荷桩变形控制方程,针对主要影响因素进行参数分析,研究表明轴向荷载对横向受荷桩承载性状的影响程度与两者的相对大小有关。当轴向荷载相对较大时,应重视轴向荷载对桩身内力和挠曲变形的影响,此时轴向荷载的存在对于柔性桩上部的内力和侧向挠曲影响比较显著,对于其深部的影响相对较小;地基系数呈线性增加时,轴向荷载对横向受荷桩的影响较为显著,而地基系数为常数时,其影响则不明显;除轴向荷载接近于屈曲荷载外,沿桩身的轴向荷载变化对水平桩的挠曲和弯矩影响甚微,轴向力作为常量的假定一般可满足工程设计的要求。

Parameter Analysis of Effects of Axial Load on the Lateral Response of Piles

Based on the small deformation assumption,the equations of the laterally loaded piles influenced by the axial load were established.The effect of axial load on the lateral response of piles was studied with parameter analysis.The analysis shows that internal force and deformation of laterally loaded pile under axial loading is actually closely linked with the values of axial and lateral loads.In general,the high level axial load should be focused on.It is more significant that the effect of axial load on the internal force and lateral deflection of the upper part of flexible piles,while there is little effect on deep of long-thin pile foundation.The effect of axial load on the lateral response of pile is the largest as coefficient form of subgrade reaction increases linearly,while the effect is minimal as coefficient form of subgrade reaction is a constant.Except in case of buckling,the changes of axial load along the pile direction have little influence on the magnitudes of deflection and moment.The assumption that the axial load is constant with depth can meet the requirements of engineering.