可更换钢连梁超低周疲劳性能多尺度数值研究  

Multi-scale numerical study on ultra-low-cycle fatigue of replaceable steel coupling beams

作　　者：刘继兵 刘韬 LIU Jibing;LIU Tao(Yulin Construction Comprehensive Service(Project Quality and safety Supervision Station for Construction),Shaanxi Yulin 719000,China;College of Civil Engineering,Tongji University,Shanghai 200092,China;Key Laboratory of Earthquake Engineering and Engineering Vibration,Institute of Engineering Mechanics,China Earthquake Administration,Harbin 150080,China)

机构地区：[1]榆林市建筑业综合服务中心(建设工程质量安全监督中心站),陕西榆林719000 [2]同济大学土木工程学院,上海200092 [3]中国地震局工程力学研究所地震工程与工程振动重点实验室,黑龙江哈尔滨150080

出　　处：《西安建筑科技大学学报（自然科学版）》2023年第3期385-393,共9页Journal of Xi'an University of Architecture & Technology(Natural Science Edition)

基　　金：黑龙江省科学基金基金(LH2022E123);中国地震工程与工程振动重点实验室开放专项基金项目(2021D04)。

摘　　要：为研究可更换钢连梁的超低周疲劳性能,提出一种多尺度模拟方法.在细观尺度上采用考虑循环塑性模型和超低周疲劳断裂模型的钢连梁精细化有限元模型,在宏观尺度上采用通过标定力-位移曲线的钢连梁简化模型,根据联肢墙整体模拟结果,建立精细化和简化模型的位移时程等效,实现其超低周疲劳性能高效分析.选取混合联肢墙试验作为示例,详细介绍方法流程;采用该方法对不同耦合比的联肢墙算例进行可更换钢连梁的超低周疲劳性能分析.研究结果表明:示例分析结果与试验结果吻合较好,说明该方法是合理的;在相同顶点位移下,联肢墙的耦合比越小,其连梁可更换消能梁段的变形越大,起裂时刻越早,断裂损伤系数也越大;消能梁段翼缘焊缝中心处易发生断裂;各层钢连梁设计相同时,等幅加载下连梁间起裂圈数的比值可通过同一时刻对应连梁累积塑性耗能的比值进行计算,不同楼层钢连梁起裂时的累积塑性耗能较为接近.A multi-scale simulation method was proposed for the study on ultra-low-cycle fatigue(ULCF)of replaceable steel coupling beams(SCBs).A refined finite element(FE)model of SCB,into which both cyclic plastic model and ULCF model at mesoscopic scale were implemented,was utilized.A simplified model of SCB at macroscopic scale was adopted whose parameters were calibrated by force-displacement relationship.The displacement history of the refined FE model of SCB is equivalent to that of the corresponding simplified model,which was determined via analysis results of whole coupled wall model;and then ULCF life could be investigated efficiently.The analysis procedure of the proposed simulation method(PSM)was presented in detail via selecting a coupled wall test as a sample.The ULCF analysis was conducted for the typical coupled walls with different coupling ratio using the PSM.Results show that the PSM is reasonable,which was validated by the comparison of analysis of the sample with experimental results.Under the same top lateral deflection,if the coupling ratio is smaller,the deformation of shear links will be larger,time of crack initiation earlier,and damage index of fracture greater.Creaks of shear links appear in the center of welds at flange firstly.When design of all replaceable SCBs is the same,under displacement loading with constant amplitudes,the ratio of loading numbers of creak initiation between two SCBs can be calculated approximately by the ratio of accumulated plastic energy dissipations(APEDs)of the corresponding two SCBs at the same time.As creak initiation of SCBs at different floors occurs,APEDs of the SCBs are almost identical.

关 键 词：超低周疲劳 可更换钢连梁 联肢墙 多尺度模拟 耦合比 延性断裂 累积塑性耗能 

分 类 号：TU973[建筑科学—结构工程]