Abstract: In order to explore the influence of cap thickness on the stress and deformation of the structure，numerical simulation method was used to study the variation rule of double-row anti-slide pile deformation，stress distribution and load sharing under below situations： with or without pile cap，and the cap thickness changing in 0.25 to 1.25 times of the pile diameter.It is found that the existence of the pile cap plays a key role in coordination with the former and the rear piles deformation and the distribution of internal force，which makes the forcing structure of double row pile more reasonable.Moreover，with the increase of pile cap size and stiffness，the pile internal force and deformation are decreased at a certain degree； but when the ratio of the cap thickness and the pile diameter is greater than 0.5，the reduction effect gradually decreases.Combining research results and structural requirements，it is recommended that the thickness of cap should be 1/2~3/4 of pile diameter and not less than 500 mm，and it should be ultimately determined by the force according to the cap.At the same time，it is found that the inner side of the connection between the pile and the pile cap is easy to have structural damage caused by stress concentration； therefore，the connection should be reinforced.

Key words: geotechnical engineering, double-row anti-slide pile； pile cap； structure design； numerical simulation

摘要： 为探求承台厚度变化对结构受力和变形的影响，采用数值模拟方法，研究了有无承台、及承台厚度在0.25~1.25倍桩径区间变化时，双排抗滑桩桩身变形、内力分布、荷载分担的变化规 律。研究发现：桩顶承台的存在，起到了协调前后排桩的变形和分配内力的作用，使得双排桩结构受力更合理；而且随着承台尺寸和刚度的增大，桩身内力及变形均有所降低，但承台厚度与 桩径之比超过0.5时，降低效应开始逐渐递减。综合研究结果及构造要求，建议承台厚度取为其桩身直径的1/2~3/4，且不小于500 mm，并最终按承台受力确定；桩与承台连接的内侧易出现应 力集中造成结构破坏，此处应加强配筋。

关键词: 岩土工程, 双排抗滑桩, 承台, 结构设计, 数值模拟