Spatial and temporal temperature variations in bridge structures due to changes in the surrounding climate produce movements which, if restrained, may induce stresses in the structure. Temperature effects have always been considered to be one of the critical issues that affect the performance of prestressed concrete (PC) bridges. In order to (1) develop an efficient temperature loading model for predicting bridge temperature-induced response; and (2) develop guidelines to incorporate the effects of temperature actions in reliability-based condition evaluation, numerical and analytical studies were conducted on a PC girder bridge in Oklahoma, USA. This paper focuses on the structural reliability analysis on the temperature loading action in accordance with AASHTO LRFD specification. A three-dimensional (3D) finite element method (FEM) model was established to estimate the movement and stress under temperature loading, and compared with monitoring counterparts. Then, the validated model was utilized for probabilistic analyses to assess the temperature load effects. Based on the probabilistic temperature loading model proposed in the first paper, loads and resistances statistics from published literature, reliability analyses of AASHTO LRFD limit states were performed by Monte Carlo simulation (MCS) and Rackwitz-Fiessler procedure to determine the safety level in terms of reliability index.

由于周围气候的变化，桥梁结构中的空间和时间温度变化会产生运动，如果受到限制，可能会在结构中产生应力。温度效应一直被认为是影响预应力混凝土（PC）桥梁性能的关键问题之一。为了 (1) 开发一种有效的温度载荷模型来预测桥梁温度引起的响应；(2) 制定指导方针，将温度作用的影响纳入基于可靠性的条件评估中，在美国俄克拉荷马州的 PC 梁桥上进行了数值和分析研究。本文重点研究了符合 AASHTO LRFD 规范的温度载荷作用的结构可靠性分析。建立了三维 (3D) 有限元法 (FEM) 模型来估计温度载荷下的运动和应力，并与监测对应物进行比较。然后，利用经过验证的模型进行概率分析，以评估温度负载的影响。基于第一篇论文中提出的概率温度载荷模型、已发表文献中的载荷和电阻统计数据，通过蒙特卡罗模拟 (MCS) 和 Rackwitz-Fiessler 程序对 AASHTO LRFD 极限状态进行可靠性分析，以确定安全水平可靠性指标。