尚志刚 郑淏 郑山锁 董晋琦 贺金川

摘   要：对5榀一般大气环境下锈蚀RC框架梁进行拟静力试验，分析锈蚀程度对RC框架梁滞回性能的影响. 基于试验结果，结合完好RC框架梁骨架曲线特征点参数，得到锈蚀RC框架梁骨架曲线模型. 引入基于能量耗散的循环退化指数βi，提出综合考虑锈蚀RC框架梁构件基本强度退化、软化段强度退化、卸载刚度退化和再加载刚度退化的滞回规则，进而建立适用于一般大气环境下锈蚀RC框架梁的恢复力模型. 将建立的恢复力模型与试验滞回曲线进行对比，吻合情况良好，表明所建立的恢复力模型具有较高的精度，能较好地揭示一般大气环境下锈蚀RC框架梁的滞回特性. 研究成果可为锈蚀RC结构弹塑性分析提供理论依据.

关键词：一般大气环境;RC框架梁;锈蚀;骨架曲线模型;循环退化;恢复力模型

中图分类号：TU375;TU317.1                   文献标志码：A

Abstract：A quasi-static test was carried out on five corroded RC frame beams in general atmospheric environment to analyze the influence of corrosion degree on hysteretic behavior. Based on the test results and the characteristic point parameters of the intact RC frame beams skeleton curve， the skeleton curve model of corroded RC frame beams was obtained. The cyclic degradation index βi based on hysteresis energy dissipation was introduced， and the hysteretic rules considering the basic strength degradation， post-capping strength degradation， unloading stiffness degradation and reloading stiffness degradation of corroded RC frame beams were proposed. Then， the restoring force model applied to corroded RC beams in general atmospheric environment was established. The comparison of the established restoring force model and the experimental hysteresis curves was performed. The results showed that the agreement was good， and the established restoring force model has high precision， which can better reveal the hysteretic behavior of corroded RC frame beams in general atmospheric environment. This study can provide a theoretical basis for the elasto-plastic analysis of corroded RC structures.

Key words：general atmospheric environment;RC frame beam;corrosion;skeleton curve model;cyclic degradation;restoring force model

隨着工业化的快速发展，我国已成为世界第三大酸雨区[1]. 酸雨不仅会造成严重的环境污染，还会极大地威胁到混凝土建筑物的安全与寿命[2]. 已有研究表明，酸雨中的SO2-4 、NO-3等侵蚀离子的共同作用，会造成RC结构中的钢筋锈蚀，进而导致纵筋有效截面减小与力学性能退化，且锈蚀产物膨胀还会削弱钢筋与混凝土间的黏结性能，从而引起RC结构滞回性能的劣化[3]. 因此研究并揭示酸雨环境下钢筋混凝土结构滞回性能劣化规律极为重要. 然而，目前国内外对一般大气环境下RC框架梁的研究多集中于……