CFRP中等约束钢筋混凝土方柱反复受压本构模型

发布时间：2018-06-24 05:51

本文选题：碳纤维 + 约束混凝土　；参考：《湖南大学学报(自然科学版)》2014年04期

【摘要】：为填补FRP约束混凝土滞回本构模型的空白,对边长305mm,高915mm及边长204mm,高612mm两种尺寸的CFRP约束钢筋混凝土方柱,采用500t四棱柱压力试验机进行了单调及反复轴压试验.试验结果表明,大尺寸CFRP约束钢筋混凝土方柱的应力-应变关系曲线存在软化段,CFRP的约束作用为中等约束,且尺寸效应对CFRP的有效约束作用有明显影响;箍筋对单调受压应力-应变曲线形状、极限压应变、反复受压卸载曲线和残余应变影响均较大.基于试验结果提出了考虑钢筋、尺寸效应及CFRP包裹层数等影响参数的CFRP中等约束混凝土方柱的反复受压本构模型.模型由描述包络线的单调受压本构模型、曲线形式的卸载曲线及直线形式的再加载曲线3部分组成,模型预测结果与试验结果吻合较好.
[Abstract]:In order to fill in the blank in the model of FRP-confined concrete hysteretic constitutive model, the monotonic and repeated axial compression tests were carried out on CFRP-confined reinforced concrete square columns with 305mm side length, 204mm side length and 204mm edge length, and high 612mm size by using a 500t four-prism pressure tester. The experimental results show that the stress-strain relationship curve of large-size CFRP confined reinforced concrete square columns has moderate constraint of softening section CFRP, and the size effect has obvious influence on the effective constraint of CFRP. The effects of stirrups on the shape of monotone stress-strain curve, ultimate compressive strain, repeated compression unloading curve and residual strain are significant. Based on the experimental results, a constitutive model of CFRP medium confined concrete square columns under repeated compression is proposed, which takes into account the influence of steel bar, size effect and the number of CFRP enclosing layers. The model consists of three parts: the monotone compression constitutive model describing the envelope, the unloading curve in the form of curve and the reloading curve in the form of a straight line. The predicted results of the model are in good agreement with the experimental results.
【作者单位】：结构工程灾变与控制教育部重点实验室(哈尔滨工业大学);哈尔滨工业大学土木工程学院;中煤科工集团沈阳设计研究院有限公司;
【基金】：国家自然科学基金资助项目(51078109,51278150) 深圳市科技研发资金基础研究重点项目(JC201005250051A)
【分类号】：TU352;TU375.3

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