挤扩支盘桩单桩竖向承载力可靠度分析

RELIABILITY ANALYSIS OF VERTICAL BEARING CAPACITY OF SINGLE SQUEEZED BRANCH PILE

首先,阐述了挤扩支盘桩的优点及其承载力可靠度分析的必要性,引用无量纲随机变量的极限状态方程,结合收集到的试桩资料进行可靠度分析;然后,采用JC法计算可靠指标β,并分析了荷载效应比、总安全系数和荷载组合形式对可靠指标的影响;最后,在分析现有试桩资料的基础上得出支盘桩的可靠指标大于等截面桩的可靠指标的结论,对挤扩支盘桩的可靠性设计作了初步探索。

At first, an expatiation of the virtue of squeezed branch piles is made. On the basis of the plenty of test data of squeezed branch piles, the reliability analysis of the vertical ultimate bearing capacity of single pile is made by using the limit state equation of dimensionless random variables. The reliability index β is calculated by the method of JC method. What is more, the influence of loading effect ratio, general safety factor and different load compositions on the reliability index is also discussed. At last, based on the analysis of the data of squeezed branch piles test, the conclusion that the reliability index β of squeezed branch piles outclasses that of the same section piles is drawn.