拉弯组合荷载下CFRP加固钢板表面裂纹应力强度因子分析  

ANALYSIS OF STRESS INTENSITY FACTORS OF SURFACE CRACKS IN STEEL PLATES STRENGTHENED WITH CFRP SUBJECTED TO COMBINATION OF TENSILE AND BENDING LOADS

作　　者：孟兮 郑云[1] 陈煊[1] MENG Xi;ZHENG Yun;CHEN Xuan(National Engineering Research Center for Steet Construction, Central Research Institute of Building and Construction Co Ltd, MCC, Beijing 100088, China;School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, China)

机构地区：[1]中冶建筑研究总院有限公司国家钢结构工程技术研究中心,北京100088 [2]北京交通大学土木建筑工程学院,北京100044

出　　处：《钢结构》2017年第11期16-20,共5页Steel Construction

基　　金："十三五"国家重点研发计划(2016YFC0701303);国家自然科学基金(51578559)

摘　　要：采用"三维实体-弹簧-壳"有限元模型对承受拉弯组合荷载的CFRP加固钢板表面裂纹应力强度因子(SIF)进行计算,并研究了拉弯应力比、裂纹特征及粘贴层数等因素对加固效果的影响。研究结果表明:采用CFRP加固,可显著降低钢板半椭圆表面裂纹前缘的应力强度因子;最大名义拉应力相同的条件时,CFRP的加固效果随拉弯应力比的增大而降低;裂纹特征对加固效果影响较大,对于裂纹面面积较大及形状扁平的裂纹CFRP会取得更好的加固效果;增加CFRP层数能在一定程度上提升加固效果,但加固效果与其粘贴层数并不成正比,需考虑胶层传递荷载能力以免造成材料的浪费。The stress intensity factors（ SIF） of the semi-elliptical surface cracks in steel plate strengthened with carbon fiber-reinforced polymer （CFRP） under combination of tensile and bending loads was calculated with the ＂ solid-springshell＂ model. Then several influencing factors on the reinforcement effects, including the tensile-flexural stress ratio, crack characteristics and the layers of CFRP, were investigated. The results showed that, CFRP strengthened significantly reduced the stress intensity factors of the semi-elliptical surface cracks in steel plate; the reinforcement effect of CFRP decreased with the tensile-flexural stress ratio increasing on the premise of the same maximum nominal tensile stress ; larger surface crack and a flat shape were favorable to the reinforcement effect enhancing; number of CFRP layers increasing could improve the reinforcement effect to a certain extent, but the reinforcement effect was not proportional to the layer numbers. It was necessary to consider the transmission capacity of the adhesive layer to avoid material waste.

关 键 词：CFRP 半椭圆表面裂纹 应力强度因子 拉弯组合荷载 有限元 

分 类 号：TU391[建筑科学—结构工程]