建筑结构钢材及其焊缝循环微观损伤模型的韧性参数校正分析  

CORRECTION ANALYSIS OF TOUGHNESS PARAMETERS OF CYCLIC MICROSCOPIC DAMAGE MODEL FOR BUILDING STRUCTURAL STEEL AND ITS WELDS

作　　者：王元清[1] 关阳 刘明[3] 卜宜都 刘希月 顾浩洋 WANG Yuan-qing;GUAN Yang;LIU Ming;BU Yi-du;LIU Xi-yue;GU Hao-yang(Laboratory of Civil Engineering Safety and Durability of China Education Ministry,Tsinghua University,Beijing 100084,China;Beijing ZhuZong Real Estate Development Co.,Ltd,Beijing 100020,China;Department of Civil Engineering,Shenyang Jianzhu University,Shenyang 110168,China;College of Aerospace Science and Engineering,National University of Defense Technology,Changsha 410073,China)

机构地区：[1]清华大学土木工程安全与耐久教育部重点实验室,清华大学土木工程系,北京100084 [2]北京住总房地产开发有限责任公司,北京100020 [3]沈阳建筑大学土木工程学院,沈阳110168 [4]国防科技大学空天科学学院,长沙410073

出　　处：《工程力学》2020年第S01期20-31,共12页Engineering Mechanics

基　　金：国家自然科学基金项目(51678339)。

摘　　要：为预测Q235B和Q345B钢材循环荷载作用下的断裂,该文以适用于超低周疲劳断裂预测的微观力学模型退化有效塑性应变模型(DSPS)和循环孔穴扩张模型(CVGM),进行缺口圆棒循环加载试验,并结合有限元软件ABAQUS,校正Q235B和Q345B普通钢材基于微观机理的超低周疲劳断裂预测模型参数。试验分别从Q235B和Q345B母材、焊缝熔敷金属及热影响区取样并加工成缺口圆棒,在两种加载制度条件下,进行超低周循环加载试验,并利用有限元对钢材断裂进行预测。研究结果表明:Q235B钢材较Q345B钢材表现出了较好的延性,但耗能总体弱于Q345B钢材;CVGM模型的预测比DSPS模型预测更加精准,在C-PTF加载制度下微观损伤模型预测程度好于CTF加载制度。CVGM模型与DSPS模型均可较准确预测循环荷载下的断裂。In order to predict the fractures of Q235B and Q345B steel under cyclic loading,the authors used the micromechanical model degeneration of the effective plastic strain model(DSPS)and the cyclic hole expansion model(CVGM)for ultra-low-cycle fatigue fracture prediction to perform the cyclic loading test of notched round bars.The test,combined with the finite element software ABAQUS,calibrates the parameters of the ultra-lowcycle fatigue fracture model for Q235B and Q345B ordinary steel based on the microscopic mechanism.The test samples from Q235B and Q345B base metal,weld deposit metal and heat affected zone were sampled and processed into notched round bars.Ultra-low cycle load tests were performed under two loading conditions,and the fractures were performed using finite element method prediction.The results show that:the Q235B steel exhibits better ductility than that of Q345B steel,but the energy consumption is generally weaker than that of the Q345B steel.The prediction of the CVGM model is more accurate than that of the DSPS model.The prediction accuracy of the microscopic damage model under the C-PTF loading system is good.In the CTF loading system.Both CVGM model and DSPS model can accurately predict the fracture of steel and its welds under cyclic loading.

关 键 词：Q235B Q345B DSPS模型 CVGM模型 有限元 预测断裂 

分 类 号：TU511.3[建筑科学—建筑技术科学]