双层地基横向受荷桩简化计算方法研究

现行规范采用按深度加权的双层地基横向受荷桩的简化计算方法,忽略了桩身挠曲变形对地基抗力的重要影响,与基桩实际受力不符,计算误差较大。在考虑桩身挠曲曲线及深度影响的基础上,采用三角形综合权函数,并引入经验弯矩修正系数,得到了双层地基当量m值的计算公式。并对桩径、土层厚度及地基比例系数等进行较大范围变化组合的情况下,与规范及精确解进行了比较分析。结果表明,该方法计算简单,精度较高。

Research about Simplified Calculation Method of Laterally-loaded Piles in Double-layered Foundation

The simplified calculation method specified by current Code about how to evaluate the loading condition of the laterally-loaded piles in double-layered foundation,by use of depth based weight function which neglect the reaction arising from the pile deflection,not in conformity with the fact,and result in big errors.Taking into account of the pile deflection and the depth influence,a triangle based weighting function is adopted combined with correctoin coefficient of moment to get a computing formula of equivalent m of the double layered foundation.By changing the combination of the diameter of piles,the thickness of the earth layers and the foundation coefficients and comparing with the calculation results with those from the Code specified formula and the accurate power series method,it is shown that the method dovetails with the accurate power series method.