基于模糊失效准则的生土窑居可靠度分析

Reliability analysis of earth-sheltered dwellings based on fuzzy failure criterion

为揭示生土窑居在役百年或数百年的深层次原因,分析了其在模糊失效准则下的可靠性。基于强度折减法,建立生土窑居的基本失效判据,用模糊区间、隶属函数表征失效准则的模糊性,用不含交叉项的二次多项式响应面函数代表生土窑居的功能函数,在不同的随机变量组合下进行可靠度分析。对河南三门峡陕县的生土窑居的模糊可靠度进行了分析,表明该地区生土窑居可靠性较高,黄土较高的粘聚力是营造生土窑居的天然有利条件,窑腿宽度对其可靠性有着重要的影响。

In order to uncover the reason why earth-sheltered dwellings have been in-service for hundreds of years, the reliability of the dwellings is investigated using fuzzy failure criterion. Based on the strength reduction method, the basic failure criterion is established. The fuzzy property of failure criterion is characterized by fuzzy interval and membership function and the performance function of earth-sheltered dwellings is expressed by the quadratic polynomial without cross term. Reliability is analyzed under different combination of random variables. The reliability analyses of the earth-sheltered dwellings in Shan city, Henan province shows that the reliability index of earth- sheltered dwellings is high. The high cohesion of loess may contribute to the earth-sheltered dwellings＇ construction and the cave leg width has significant influence on reliability.