中文摘要：

为深入研究水平荷载作用下的单桩响应和桩土相互作用机理,引入了三参数法水平荷载桩的挠曲线微分方程;基于已有的地基反力系数为常数时桩的变形和内力的解析解,以及桩的响应的连续性,提出了半解析解。采用Fortran语言编制了计算程序,并通过特例情况下的解与已有解进行对比来验证所得解的可靠性。计算结果表明：桩长较大时,桩底的边界条件对桩的响应影响较小;地基反力系数中的指数以及反映地表处土抵抗侧向变形能力的参数对桩的响应影响较大,不容忽略;该解不仅有效,而且具有广泛的应用性。

英文摘要：

In order to investigate the responses of laterally loaded single piles and the principle of the pile-soil interaction,the deflection curve differential equation based on the three-parameter method was introduced.Based on the pre-existing analytical solutions for laterally loaded piles in which the coefficient of subgrade reaction was assumed to be a constant and the continuity principle of pile responses,the semi-analytical solutions were submitted.The relevant computer program was developed by Fortran programming,and the obtained solutions were verified by comparing them with the pre-existing solutions corresponding to a special case.The calculation results indicated that the boundary condition at the pile tip plays a marginal role in pile responses when the pile length is comparatively great,the influences of two parameters from the coefficient of subgrade reaction,including the index and the parameter which represents the ability of soil at the ground surface to resist the lateral deflection on pile responses are too great to be ignored,and the obtained solutions are effective and can be applied widely.