摘要
为研究CFRP加固承载状态下圆钢管混凝土轴压短柱的屈服承载力,首先推导CFRP加固非承载状态下圆钢管混凝土短柱的屈服承载力,进而对CFRP加固承载状态下圆钢管混凝土轴压短柱屈服承载力的计算式进行了推导。建立了非承载状态下圆钢管混凝土的有限元模型,通过已有试验结果,验证了有限元建模方法的有效性。采用该方法对不同参数的CFRP加固承载状态下圆钢管混凝土短柱建立有限元模型,有限元模拟的屈服承载力与理论计算结果吻合良好,证明了理论公式的准确性。基于所建立的有限元模型和提出的理论公式,分析不同承载率、不同钢管厚度和不同CFRP加固层数等因素对轴压短柱屈服承载力的影响。结果表明:初始承载率影响CFRP的约束效果,屈服承载力随着初始承载率的提高而降低,而CFRP层数的增加则放大了这种效应;增加CFRP加固层数可以有效提高承载状态下构件的屈服承载力,CFRP加固承载状态下圆薄壁钢管混凝土轴压短柱性能更优。
To study the yield strength of CFRP-strengthened concrete-filled circular steel tubular stubs under initial loading state, equations for calculating the yield strengths of CFRP-strengthened concrete-filled circular steel tubular stub columns with and without initial loads are both deduced. The finite element(FE) models for concrete-filled circular steel tubular stubs without initial loads are established, which are verified through comparisons with existing experimental results. Using the similar method, FE models of CFRP-strengthened concrete-filled circular steel tubular stubs with different parameters under initial loads are also established. The yield strengths obtained from the FE simulations agree well with the theoretical calculations, which verifies the accuracy of the proposed equations. Based on the established FE model and the theoretical equations, the effects of different parameters, including loading rate, wall thickness and number of CFRP layers, on the yield strength of CFRP-strengthened concrete-filled circular steel tubular stub columns under initial loads are analyzed and discussed. The results indicate that the initial loading rate has a certain influence on the confinement of CFRP. The yielding strength reduces with the increase of the initial loading rate, while more CFRP layers can amplify this phenomenon. The yield strength can be increased efficiently by increasing the number of CFRP layers. The CFRP-strengthening method is more effective when the wall thickness of the steel tube in concrete-filled circular steel tubular stub columns is smaller.
作者
熊川楠
邵永波
陈振明
XIONG Chuannan;SHAO Yongbo;CHEN Zhenming(School of Civil Engineering and Geomatics,Southwest Petroleum University,Chengdu 610500,China;China Construction Steel Structure Co.,Ltd.,Shenzhen 518000,China)
出处
《建筑结构学报》
EI
CAS
CSCD
北大核心
2021年第8期73-83,共11页
Journal of Building Structures
基金
四川省青年科技创新团队项目(2019JDTD0017)。
关键词
圆钢管混凝土
CFRP加固
承载状态
理论公式
有限元模型
屈服承载力
concrete-filled circular steel tube
CFRP strengthening
loading state
theoretical equation
finite element model
yield strength
