尚志刚 郑山锁 郑淏 姜叶子 贺钧 杨丰

摘 要：為研究酸雨腐蚀后 RC框架节点的抗震性能，采用人工气候法模拟酸雨环境，对8 榀 RC梁柱节点试件进行加速腐蚀试验，而后进行拟静力试验，观察酸雨腐蚀后试件表观现 象，并分析腐蚀循环次数、轴压比及硫酸根离子浓度对节点与其核心区破坏特征、滞回性能、剪切性能、受剪承载力等的影响.在此基础上，引入损伤指数，并确定损伤模型参数取值，进而 定量化揭示节点试件在加载过程中的损伤演化规律.试验与分析结果表明：酸雨腐蚀虽会使 试件发生骨料外露、结晶析出、蚀洞形成等现象，但腐蚀后试件的核心区最大剪力仍小于现行规范计算的抗震受剪承载力阈值;随着腐蚀循环次数与硫酸根离子浓度的增加，试件梁端弯曲裂缝与核心区剪切裂缝出现较早且发展较快，节点承载能力、变形能力与耗能能力均逐渐 减小，而核心区剪切占比与损伤发展速率则不断变大;具有较大轴压比的试件，节点承载能力相对较大，但变形能力较差，核心区剪切占比及损伤发展速率较大.

关键词：酸雨环境;RC梁柱节点;拟静力试验;滞回性能;剪切性能;损伤演化中图分类号：TU375.4，TU317.1 文献标志码：A

Experimental Study on Seismic Behavior of RC Frame Joints under Acid Rain Environment

SHANG Zhigang1，2，ZHENG Shansuo1，2?，ZHENG Hao3，JIANG Yezi4，HE Jun4，YANG Feng4

（1.School of Civil Engineering，Xian University of Architecture and Technology，Xian 710055，China;

2.Key Laboratory of Structural Engineering and Earthquake Resistance of Ministry of Education（XAUAT），Xian 710055，China;

3.School of Combat Support，Rocket Force University of Engineering，Xian 710025，China;

4.China Qiyuan Engineering Corporation，Xian 710018，China）

Abstract：To study the seismic behavior of reinforced concrete（RC）frame joints affected by acid rain corro-sion，the artificial climate method was used to simulate the acid rain environment.The accelerated corrosion tests were conducted on eight RC beam-column joint specimens，and then quasi-static tests were carried out.The appar-ent phenomenon of the specimens corroded by acid rain was observed.The influence of corrosion cycles，axial com-pression ratio and sulfate ion concentration on the failure characteristics，hysteretic behavior，shear performance and shear capacity of the RC frame beam-column joints were analyzed.On this basis，the damage index was intro-duced，and the parameters of damage model were determined.Then，the damage evolution of the specimens during the loading process was revealed quantitatively.The results of test and analysis show that，aggregate exposure，crys-tal precipitation and eroded holes appear on the specimens due to acid rain corrosion，but the maximum shear force of corroded joint core area is still less than the threshold of the seismic shear capacity calculated by the current Chi-nese standard.With the increase of corrosion cycles and sulfate ion concentration，the bending cracks at the beam and the shear cracks at the core area appear earlier and develop rapidly，and the bearing capacity，deformation ca-pacity，energy dissipation capacity decreased gradually，while the shear proportion and damage development rate in-crease continuously.For the specimen with a larger axial compression ratio，the bearing capacity is relatively large，while the deformation capacity is poor，and the shear proportion and damage development rate increase are large.

Key words：acid rain environment;RC beam-column joints;quasi-static test;hysteretic behavior;shear perfor-mance;damage evolution

根据我国生态环境部发布的报告，截至2018年，我国长江以南— 云贵高原以东的部分地区仍属于酸雨区，酸雨类型总体为硫酸型[1].处于酸雨环境中的钢筋混凝土（Reinforced Concrete，RC）结构会受到H+、SO42-、NO3-等离子的侵蚀，进而造成其抗震性 能劣化[2-3].因此……