结构可靠性分析的概率和非概率混合模型

在结构可靠性分析中需要合理地定量处理影响结构性能的诸多不确定性。不确定性的模拟既可以是概率的，也可以是非概率的。文中简要介绍结构可靠性分析的概率方法和基于区间模型的非概率可靠性方法。提出结构可靠性分析的概率和非概率混合模型。通过两级功能方程的逐次建立及可靠性分析，给出结构可靠的概率度量。实例分析说明在结构可靠性分析中，应根据不确定性的产生机理及所掌握的数据信息合理地选取分析模型。

HYBRID PROBABILISTIC AND NON-PROBABILISTIC MODEL OF STRUCTURAL RELIABILITY

In most mechanical and structural systems, a certain amount of uncertainties exist in material and geometrical properties, applied loads, etc. These uncertainties must be taken into account reasonably when estimating the reliability of systems. The modeling of uncertainties may be either probabilistic when sufficient information is available, or non probabilistic convex models when available data are lack or limited. The structural reliability theories of probabilistic and the non probabilistic method based on interval analysis were briefly introduced. A hybrid probabilistic and non probabilistic approach for structural reliability analysis was presented. In our approach, through a successively construction of performance equations in two levels and correspondingly reliability analysis, the probability that a structure is reliable may be given. A practical example illustrated the application of the proposed theory. It is also shown that when available information about some parameters is lack, the probabilistic assumption may lead to under conservative results.