This paper uses the spectral stochastic finite element method (SSFEM) for analyzing reinforced concrete (RC) beam/slab problems. In doing so, it presents a new framework to study how the correlation length of a random field (RF) with uncertain parameters will affect modeling uncertainties and reliability evaluations. It considers: 1) different correlation lengths for uncertainty parameters, and 2) dead and live loads as well as the elasticity moduli of concrete and steel as a multi-dimensional RF in concrete structures. To show the SSFEM’s efficiency in the study of concrete structures and to evaluate the sensitivity of the correlation length effects in evaluating the reliability, two examples of RC beams and slabs have been investigated. According to the results, the RF correlation length is effective in modeling uncertainties and evaluating reliabilities; the longer the correlation length, the greater the dispersion range of the structure response and the higher the failure probability.

本文使用谱随机有限元法 (SSFEM) 分析钢筋混凝土 (RC) 梁/板问题。为此，它提出了一个新的框架来研究具有不确定参数的随机场 (RF) 的相关长度将如何影响建模不确定性和可靠性评估。它考虑：1) 不确定参数的不同相关长度，2) 恒载和活载以及混凝土和钢的弹性模量作为混凝土结构中的多维 RF。为了显示 SSFEM 在混凝土结构研究中的效率并评估相关长度效应在评估可靠性方面的敏感性，我们研究了 RC 梁和板的两个示例。根据结果​​，RF相关长度在建模不确定性和评估可靠性方面是有效的；相关长度越长，结构响应的离散范围越大，失效概率越高。