扩底桩荷载传递机理及承载力确定方法研究

桩的荷载传递规律分析和桩基础承载力的确定历来被认为是桩基础设计中最困难的问题之一。根据地基土的物理力学性质指标和静载荷试验结果，基于非线性弹性理论，对桩基静载荷试验资料分析及其承载力确定方法的研究，研究发现，桩端承载力和桩侧摩阻力的比值与桩顶倚载关系曲线具有明显的阶段性，与现场静荷载试验资料具有较好的一致性，可以较方便地用来分析和确定单栅极限承载力。该方法具有比静载倚试验的荷载-沉降曲线法更安全、准确、方便等优点。

STUDY ON LOAD TRANSFER AND DETERMINATION METHOD OF BEARING CAPACITY FOR ENLARGED PILE

So far, the load transfer mechanism and the determination method of bearing capacity of pile are being also considered as one of the most difficult problems for pile foundation design. According to the physic mechanics parameters of soil and the static load experimental results of piles, and based on the nonlinear elastic theory, the pile bearing capacity and test results were all studied herein. The research results confirmed that the relation curves of load acted on the pile top and the ratio of point resistance to lateral friction of pile have distinct phase characters. The result agrees well with that of static load test. Those relation curves can be used to determine the ultimate bearing capacity conveniently for enlarged pile. Compared with the past used determination method of the load beating capacity according to the load-settlement curves from static load tests, this new method has distinct advantages of more safety.