关键词: 失效概率矩独立全局灵敏度指标, 灵敏度分析, 乘法降维, Edgeworth级数, 积分网格, 前四阶整数矩

Abstract: The moment-independent global reliability sensitivity analysis can provide useful information for guiding the reliability-based design optimization. This paper proposes an efficient algorithm for moment-independent global reliability sensitivity analysis based on the multiplicative dimensional reduction technique and the Edgeworth expansion. By adopting Edgeworth expansion, the estimation of the moment-independent global reliability sensitivity index is approximately converted into the estimations of the unconditional and the conditional first four-order moments of the model output and is efficiently estimated by employing the multiplicative dimensional reduction technique. Based on this technique, this paper derives the algorithms of the conditional first four-order moments and the outer expectation of the sensitivity index by repeatedly assembling the information in the integration grid obtained from the estimation process of the unconditional first four-order moments of model output. The proposed algorithm improves the efficiency for analyzing the moment-independent global reliability sensitivity. The analyses of an aeroengine turbine disk and an automobile front axle demonstrate the efficiency and accuracy of the proposed method in estimating the moment-independent global reliability sensitivity index.

Key words: moment-independent global reliability sensitivity index, sensitivity analysis, multiplicative dimensional reduction technique, Edgeworth expansion, integration grid, first four-order moments