Time-dependent reliability and sensitivity analysis, in which the nature of demand, capacity and the limit state function varies over the life cycle of the structural system, is a challenging task. Meta-models are a suitable tool to construct inexpensive-to-evaluate and accurate surrogates in analysis of modern engineering problems. The paper’s contribution is threefold: First, the superiority of polynomial chaos Kriging (PCK) meta-model in terms of efficiency and accuracy is depicted in comparison to two other state-of-the-art methods in an explicit representation of a pilot gravity dam. Second, the problem of aging dams is analytically studied. Adaptive reliability approaches which benefit from Kriging and PCK meta-models are also investigated in a comparative analysis with classical reliability methods. Third, the importance of considering nonlinear dependency between random variables by copula theory is investigated under the reliability and sensitivity concepts. The results show that PCK meta-model can be used as an effective technique in uncertainty quantification (UQ) of dams. Furthermore, Kriging and PCK-assisted reliability methods can establish fairly accurate meta-models to perform reliability analysis in structural UQ with low computational efforts. Finally, the concept of UQ is propagated to ”dam class” in which the dam shape and its age are assumed to be variable. A generalized program is developed to assist dam owners and decision-makers in approximate failure probability estimation of gravity dams. This paper paves the road for global risk assessment of dams.

瞬态可靠性和敏感性分析，其中需求的性质、容量和极限状态函数在结构系统的生命周期内变化，是一项具有挑战性的任务。元模型是构建现代工程问题分析中成本低廉且准确的替代品的合适工具。该论文的贡献有三方面：首先，与其他两种最先进的方法相比，多项式混沌克里金 (PCK) 元模型在效率和准确性方面的优势被描述为导向重力坝的显式表示. 其次，对大坝老化问题进行了分析研究。在与经典可靠性方法的比较分析中，还研究了受益于克里金法和 PCK 元模型的自适应可靠性方法。第三，在可靠性和敏感性概念下研究了通过copula理论考虑随机变量之间非线性相关性的重要性。结果表明，PCK元模型可以作为一种有效的大坝不确定性量化（UQ）技术。此外，克里金法和 PCK 辅助可靠性方法可以建立相当准确的元模型，以较低的计算量在结构 UQ 中执行可靠性分析。最后，UQ 的概念被传播到“大坝等级”，其中大坝形状和年龄被假定为可变的。开发了一个通用程序来帮助大坝所有者和决策者估计重力坝的近似失效概率。本文为全球大坝风险评估铺平了道路。