中文摘要：

多元复合地基是将复合地基中的三种桩型中的两种或三种联合应用于加固软土地基，从而大幅度提高地基承载力，减小地基沉降。但是多元复合地基的设计理论和计算方法并不成熟，承载力发挥系数无法精确选取。从单桩型复合地基关于桩间土承载力发挥系数与桩土应力比的关系式出发，并在得到多元复合地基桩土应力比的解析解的基础上，推导出多元复合地基次桩和桩间土承载力发挥系数的一般求解法。通过实例，证明了求解方法的可行性。

英文摘要：

Multi-pile composite foundation is to use two or three kinds of piles to reinforce soft clay ground. It can increase the bearing capacity and dihainish the settlement. Because of the design-theory and the method of calculation are not mature, so that the efficiency factor of bearing capacity can not be selected accurately. With the relationship between efficiency factors of soil and pile-soil stress ratio, based on the analytical solution of pile-soil stress ratio in multi-pile composite foundation, the common method for solving efficiency factors of bearing capacity of auxiliary piles and the soil between piles in multi-pile composite foundation is presented. A practical example is given to improve the feasibility of this method.