桩土共同作用设计理论研究

对桩土共同作用理论作了初步探讨，对不同桩距下复合桩基设计方法进行了讨论。提出当桩为摩擦桩或端承摩擦桩时，刚性桩复合地基不设褥垫层比设垫层更经济、安全。认为在控制复合桩基的总安全度及变形的前提下，可明确按桩土应力比进行设计，设计桩土应力比无须等于实际桩土应力比，并对目前疏桩基础设计方法存在的问题进行了讨论，提出了改进意见。

Study on design theory of pile-soil cooperative work

The preliminary study on the effect of pile-soil cooperative work is made at first. Then the condition for formation of rigid pile composite ground and the design method for different pile spacings of composite pile foundation is discussed. When piles are friction ones and end-bearing friction ones, the rigid pile composite ground without cushion is safer and more economical than that with cushion. If the total safety level and settlement of composite pile foundation can be satisfied, design may be carried out in definite stress ratio of pile and soil; and the designed stress ratio of pile and soil is unnecessarily equal to the practical one. Some existing problems in design method of pile foundation with large spacing between piles are discussed, and some proposals of improvement are put forward, too.