摘要
为提高桥梁结构时变可靠度的计算效率,该文提出了新的计算方法。该方法基于结构时变可靠度分析的基本理论,利用Taylor级数展开,将可靠度计算从传统的积分运算形式转换为代数运算的形式,从而简化计算过程,提高计算效率。为了考虑桥梁初始承载力和衰减过程的不确定性,该文基于全概率方法,给出了计算劣化结构时变可靠度的显式公式。通过将该文方法应用于某钢筋混凝土桥梁进行时变可靠度分析,并与MonteCarlo模拟方法进行对比,表明了该文方法的准确性和高效性。
A new method was proposed to improve the calculation efficiency of time-dependent reliability analysis for bridges. Based on the basic theory of structural reliability, the proposed method utilizes the Taylor expansion to simplify the traditional formula in an integration expression as a new formula in an algebraic expression, which essentially improves the calculation efficiency. In order to consider the uncertainties associated with the initial resistance and the degradation process, an explicit formula for time-dependent reliability analysis was also presented using a total probabilistic theorem. The proposed method was applied to the time-dependent reliability analysis of an RC bridge, and the results were compared with that associated with Monte Carlo simulation method to demonstrate the accuracy and high efficiency of the new method.
引文
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