Uncertainty will inevitably be introduced into the structural analysis, while randomness is an important manifestation of uncertainty. Based on the random field theory, the correlated random fields of the Koyna gravity dam were realized, and the influence of the randomness of material parameters on the nonlinear responses of the gravity dam was investigated. A concrete continuum crack model was employed to describe the nonlinear mechanical behavior of gravity dams under static and dynamic loads. To avoid the contingency caused by the initial random samples, the comparisons of the nonlinear dynamic responses of the dam are based on the statistical analysis of a large number of random fields. The parameter sensitivity analysis is first implemented, and then, the nonlinear responses of the proposed correlated random field model and the conventional random variable-based model are comprehensively compared. The analysis showed that the randomness and spatial correlation of materials would affect the seismic performance of gravity dams, which should be considered in structural design and seismic risk analysis.

不确定性将不可避免地引入结构分析中，而随机性则是不确定性的重要体现。基于随机场理论，实现了科伊纳重力坝的相关随机场，研究了材料参数随机性对重力坝非线性响应的影响。用混凝土连续裂缝模型描述了重力坝在静态和动态载荷下的非线性力学行为。为避免初始随机样本引起的偶然性，大坝非线性动力响应的比较是基于对大量随机场的统计分析。首先执行参数敏感性分析，然后，综合比较了所提出的相关随机场模型和常规的基于随机变量的模型的非线性响应。分析表明，材料的随机性和空间相关性会影响重力坝的抗震性能，应在结构设计和地震风险分析中加以考虑。