强腐蚀后钢筋的力学退化分析及断裂模型  

Mechanical Degradation Analysis and Fracture Model of Strongly Corroded Steel Bars

作　　者：王彬 乔文靖[1] 杨帆[1] 李沂倩 李卓达 WANG Bin;QIAO Wenjing;YANG Fan;LI Yiqian;LI Zhuoda(Civil&Architecture Engineering Xi’an Technological University,Xi’an 710021,China)

机构地区：[1]西安工业大学建筑工程学院,西安710021

出　　处：《西安工业大学学报》2025年第1期91-103,共13页Journal of Xi’an Technological University

基　　金：陕西省科技厅重点研发计划项目(2024SF-YBXM-618);陕西省科技厅面上研发计划项目(2024JCF-YBMS-427)。

摘　　要：为研究强腐作用对钢筋拉伸力学性能退化和断裂机制的影响,用浓度为36%工业盐酸对27根钢筋进行腐蚀,随后开展拉伸试验,得到不同腐蚀时间下的钢筋破坏形态及应力应变关系曲线,并通过有限元分析了腐蚀时间对应力三轴度和等效塑性应变的影响,基于理论分析推导出钢筋强腐蚀断裂模型。试验结果表明:随着腐蚀时间的增加,腐蚀率增加,钢筋的延性逐渐下降,经过72 h强腐后,名义屈服强度下降4.66%,名义极限强度下降4.65%,伸长率下降12.13%,弹性模量下降12.28%。有限元分析结果表明:应力三轴度和等效塑性应变均随腐蚀时间的增加而逐渐增大。理论分析中对空穴增长(VGM)模型(the void growth)和应力修正临界应变(SMCS)模型(the stress modified critical strain)进行修正,建立了包含应力三轴度、等效塑性应变、腐蚀时间的钢筋强腐蚀断裂模型。该模型与试验结果吻合较好,可为强腐作用下钢筋的工程应用和后续研究提供参考。This paper studies the influence of strong corrosion on the degradation of tensile properties and fracture mechanism of steel bars.Tensile tests are conducted on twenty seven steel bars corroded with industrial hydrochloric acid with a concentration of 36%,from which the failure modes and stress strain relationship curves of the steel bars corroded for different times are obtained.Moreover,finite element models are used to analyze the effect of corrosion time on stress triaxiality and equivalent plastic strain.Based on theoretical analysis,the fracture model of corroded steel bars is deduced.The experimental results show that the corrosion rate of the steel bars increases and their ductility drops gradually with the increase of corrosion time.After 72 hours of strong corrosion,the nominal yield strength,the nominal ultimate strength,the elongation and the elastic modulus decrease by 4.66%,4.65%,12.13%and 12.28%,respectively.The finite element analysis shows that the stress triaxiality and equivalent plastic strain increase gradually with the extension of corrosion time.The fracture model of the corroded steel bars,including stress triaxiality,equivalent plastic strain,and corrosion time,is established by modifying the void growth model(VGM Model)and the stress Modified critical strain model(SMCS model).The model is in good agreement with the experimental results.This study can provide a reference for the engineering application of and follow up research on steel bars with strong corrosion.

关 键 词：强腐蚀 钢筋 力学退化 应力三轴性 等效塑性应变 

分 类 号：TG1[金属学及工艺—金属学]