基于区间理论的桥涵墩台基础可靠性分析

Analysis on Reliability of Pier Foundation Based on Interval Theory

根据墩台基础结构力学参数取值的区间性特征,引入区间分析理论,视墩台基础结构力学参数为区间变量,在确定墩台基础稳定可靠性分析的合理功能函数基础上,建立基于区间理论的墩台基础结构稳定非概率可靠性计算模型;针对区间运算结果扩张问题,引入改进的区间截断法,建立墩台基础稳定性非概率可靠性分析的区间运算方法,采用改进的一维优化算法计算墩台基础稳定非概率可靠度指标,进而建立基于区间理论的墩台基础稳定性非概率可靠性分析方法;将非概率可靠性分析方法应用于工程实例,计算结果验证方法的合理性与可行性。探讨结构力学参数变异性对墩台基础稳定性非概率可靠度指标的影响规律,具有一定的工程参考价值。

Firstly , on the basis of the interval features of mechanical parameters of pier foundation , the interval analysis method was introduced to establish the non-probabilistic reliability analysis method for the structural system of pier foundation , the uncertain geotechnical mechanical parameters were regarded as interval varia-bles . Then ,in terms of the limitation and shortage of the interval calculating rules , the interval-truncation approach and improved one-dimensional optimization algorithm were adopted to determine the range of func-tional functions in order to avoid the interval expansion of functional functions . Lastly , the influence of me-chanical structure parameters on non-probabilistic reliability indexes of pier foundation was studied . The re-search results show the proposed method is reasonable and feasible , and is of some engineering reference .