“荷载分离法”研究复合地基的承载机理

利用数值试验的独特优势，采用作者提出的“荷载分离法”研究了群桩复合地基复杂的承载机理和附加应力的分布规律，将“群桩—土—承台”的相互作用问题层层剖析，分别得到了“承台—土—桩”和“桩—土—桩”体系的相互作用的性状与机理，讨论了附加应力和桩侧摩阻力的分布特点，归纳了“群桩—土—承台”体系在相互作用中所表现出来的3种“削弱”与“增强”机理。比较了群桩中的一根基桩和单桩在承载性状上的区别，从而得到了一系列有意义的结论。不仅对复合地基的理论与实践的进一步发展有所裨益，也同时证明了“数值仿真试验”研究手段在岩土工程领域中的独特作用。

Bearing Mechanism of Composite Foundation with the Loading Separate Method

Based on the unique advantages of numerical test, the bearing me chanism and the distribution pattern of the additional stresses of the composite foundation with different pile-stiffness are studied systematically using a “ Loading separate method” proposed in this paper. Decomposing the problems of ht e interaction of “group pile-soil-cap”, the characteristics and the mechanis m of interaction of the “pile-soil-cap” and “pile-soil-cap” systems are stud ied separately. And the distribution characteristics of the additional stressed and the shaft resistance forces are discussed in detail, from which three weakening and strengthening mechanisms in the pile-group system interaction are induced. T he different characters of a pile of group pile and a single pile are compared f urther, and some useful conclusions are obtained.