深厚土层冻结法凿井过程中外层井壁模糊随机可靠性分析

针对常规可靠性表征结构稳定性时的不足,分析更加符合深井工况的模糊随机可靠性,给出相应的模糊随机功能函数和模糊随机极限状态方程,并针对可靠性中心点算法进行模糊随机改进。结合深厚冲积层井壁冻结压力和钢筋混凝土井壁极限承载力模糊随机分析,得到深厚冲积层高强钢筋混凝土外层井壁的模糊随机极限状态方程,应用改进后的中心点法推导出外层井壁结构模糊随机可靠性的解析区间,并提出各主要变量对模糊随机可靠性的灵敏度区间模型。工程算例表明:由于综合考虑到各参数的不确定性,获得的模糊随机可靠性相比常规的可靠性总体偏低,其结果更能反映实际工况。此外,模糊随机可靠性首次以区间值表征井筒的可靠程度,较常规可靠性的定值表现方法更具合理性。

Fuzzy random reliability analysis on outer shaft lining in the process of freezing method sinking for deep alluvium

Aiming at the shortcomings of the conventional reliability in characterization of structure stability,the fuzzy random reliability was analyzed to evaluate working condition of deep shaft lining.The corresponding fuzzy random functions and fuzzy random limit state equation were provided to improve the center point algorithm of fuzzy random reliability.Combining fuzzy random analysis with shaft freezing pressure and shaft ultimate bearing capacity,the fuzzy random limit state equation was obtained for outer shaft lining structure of high strength reinforced concrete in deep alluvium.Application of the improved center point method deduces the analytical range for the fuzzy random reliability of outer shaft lining structure,and put forward the fuzzy random reliability sensitivity range model of each variable.Engineering example shows for considering the uncertainty of all the parameters comprehensively,the fuzzy random reliability is generally lower than conventional reliability and reflects the actual engineering status better.In addition,the fuzzy random reliability with characterization of interval value is more reasonable than conventional reliability modus of fixed value manifestation.