拉索加速腐蚀试验及其引起的力学性能退化研究  

Study on cable property degradation under accelerated corrosion test

作　　者：严仁章[1,2,3] 文强 王帅[4] 孙涛 刘红波[3] 张平 Yan Renzhang;Wen Qiang;Wang Shuai;Sun Tao;Liu Hongbo;Zhang Ping(State Key Laboratory of the Mountain Bridge and Tunnel Engineering,Chongqing Jiaotong University,Chongqing 400074,China;School of Civil Engineering,Chongqing Jiaotong University,Chongqing 400074,China;Tianjin University,Tianjin 300072,China;Chongqing Aerospace Polytechnic,Chongqing 400021,China;Army Logistics Academy of PLA,Chongqing 401331,China;T.Y.LIN International Engineering Consulting(China)Co.,Ltd.,Chongqing 401121,China)

机构地区：[1]重庆交通大学省部共建山区桥梁及隧道工程国家重点实验室,重庆400074 [2]重庆交通大学土木工程学院,重庆400074 [3]天津大学,天津300072 [4]重庆航天职业技术学院,重庆400021 [5]中国人民解放军陆军勤务学院,重庆401331 [6]林同棪国际工程咨询(中国)有限公司,重庆401121

出　　处：《土木工程学报》2023年第5期18-31,共14页China Civil Engineering Journal

摘　　要：拉索作为弦支结构体系的核心构件,当其暴露于自然环境时不可避免会发生腐蚀,进而引起力学性能退化。为理清腐蚀影响因素对拉索腐蚀形态及力学性能的影响规律,通过试验研究与数值模拟相结合的方式,开展拉索腐蚀形态分析与静力性能研究。首先,制备5组共60套拉索试件,开展室内加速腐蚀及静力拉伸试验,揭示pH值、Cl^(-)浓度、腐蚀时长等因素对拉索腐蚀形态与腐蚀率的影响规律,并通过剖析腐蚀率与拉索力学性能参数间的数理关系,建立拉索考虑腐蚀影响的本构模型;然后,建立拉索截面腐蚀数值模型,分析归纳不同环境下的拉索腐蚀形态,在与试验结果对比验证的基础上,给出均匀和缝隙腐蚀的截面简化几何模型,并据此建立150套综合考虑点蚀、缝隙和均匀腐蚀不同组合的拉索精细化数值模型,计算补充拉索腐蚀后力学性能参数样本库,以弥补试验过程中腐蚀率范围较小的局限性,进而修正前述通过试验数据建立的腐蚀拉索本构模型,为在役弦支结构性能评估奠定理论基础。As the core component of cable supported structures,the cable will inevitably be corroded with degradation of mechanical properties when exposed to the natural environment.In order to clarify the influence of corrosion factors on the corrosion morphology and mechanical properties of cable,corrosion morphology and static properties of cable were studied by combining experimental research and numerical simulation.Firstly,the indoor accelerated corrosion and static tensile test were conducted on five groups of 60 sets of cable specimens and the influence laws of pH value,Cl^(-)concentration,corrosion time on cable corrosion morphology and corrosion rate were revealed.The constitutive model of cable considering the influence of corosion was established by analyzing the mathematical relationship between the corrosion rate and the cable mechanical property parameters.Then,the numerical model of cable section corrosion is established and the cable corrosion forms in different environments are analyzed and summarized.By comparing the analysis results with the experimental ones,the simplified sectional geometric model of uniform and crevice corrosion was given.150 sets of cable refinement numerical models considering different combinations of pitting corrosion,crevice and uniform corrosion were established to supplement the sample library of mechanical property parameters of corroded cable and make up the limitation of small corrosion rate range in the test process.The constitutive model of corroded cable established through the experimental data is modified,which will lay a theoretical foundation for the property evaluation of in-service cable supported structures.

关 键 词：拉索 加速腐蚀试验 腐蚀形态 腐蚀率 力学性能 

分 类 号：TU394[建筑科学—结构工程]