大尺寸CFRP约束混凝土方柱落锤动态冲击试验研究  

Experimental research on large-scale square columns confined with wrapped CFRP under drop hammer impact load

作　　者：单波[1] 刘波[1] 肖岩[1,2] GIORGIO Monti 

机构地区：[1]湖南大学建筑安全与节能教育部重点实验室,长沙410082 [2]南加州大学土木系,洛杉矶ca90089 [3]罗马第一大学建筑学院,罗马00917

出　　处：《振动与冲击》2016年第20期90-97,共8页Journal of Vibration and Shock

基　　金：国家重点基础研究发展计划(973计划)(2012CB026204);中央高校基本科研业务费项目联合资助

摘　　要：采用FRP增强的混凝土柱在使用过程中,可能受到轴向冲击荷载作用,但目前这方面的研究基本处于空白.通过对7组21个大尺寸CFRP约束混凝土方柱进行落锤轴向冲击试验,研究倒角半径r对约束柱抗冲击性能的影响.试验获取了锤头冲击力时程曲线、压缩变形时程曲线、FRP表面关键点的应变时程曲线和整个破坏过程的高速影像等信息.试验结果表明,CFRP约束混凝土方柱的破坏是由试件中部倒角位置处的CFRP被拉断所导致的,试件的破坏现象与倒角半径r有关;倒角半径r对约束柱的冲击性能有显著影响,r越大,冲击应力峰值和能量密度也越大;CFRP约束混凝土方柱的动力增大系数（DIF）随倒角半径比r.的增大而减小,基本成线性关系,在1.23-1.82之间.Concrete column confined with wrapped FRP may be suffered from axial impact loading, but the mechanical performance under axial impact of this composite structure is a blank research field. In this paper, seven groups of CFRP confined large-scale square columns with different comer radius, three specimens in each group, were conducted drop hammer axial impact tests. Comer radius r is the main test parameter. The impact force-time history curves, compressive deformation-time history curves, strain-time history curves of key points on CFRP jacket and the high-speed photography during failure process were obtained in the tests. The test results show that the fracture of CFRP jacket in the chamfer zone leads to failure of test columns and the failure characteristics of specimens is related to comer radius r. Impact strength and energy density of confined columns obviously increase with corner radius r. The relationship between dynamic increase factor （ DIF） and comer radius ratio rc almost presents a linear decrease relationship and the value varies from 1.23 to 1. 82.

关 键 词：FRP 约束混凝土柱 落锤 抗冲击性能 动态增大系数 

分 类 号：TU375.3[建筑科学—结构工程]