新型不锈钢与固废混凝土对钢管混凝土短柱高温后力学性能的影响  

Effects of New Stainless Steel and Concrete Made with By-products on the Post-fire Behavior of Concrete-filled Steel Tubular Stub Columns

作　　者：陈晨 CHEN Chen(Fujian Province Water Survey and Design Co.,Ltd.,Fuzhou,Fujian 350005,China)

机构地区：[1]福建省水投勘测设计有限公司,福建福州350005

出　　处：《水利与建筑工程学报》2023年第3期152-157,202,共7页Journal of Water Resources and Architectural Engineering

基　　金：国家自然科学基金项目(51708118)。

摘　　要：通过8根新型不锈钢管混凝土(CFSST)轴压短柱试验,考察试件的破坏模态、荷载-应变曲线、极限承载力、延性和刚度等力学性能指标,探究了新型不锈钢与固体废弃物混凝土对钢管混凝土短柱高温后力学性能的影响。研究结果表明两类新型建材对钢管混凝土短柱高温后破坏模态无明显影响,高温作用后CFST短柱的刚度和极限承载力呈下降趋势但延性提高。与传统碳素钢与普通混凝土相比,新型不锈钢与固体废弃物混凝土有效地减缓了试件高温后承载力下降幅度。引入材料强度折减系数后,我国DBJ-T13-51—2020规程计算方法可以较好地评估高温后该类钢管混凝土短柱的剩余承载力。随后利用通用有限元软件ABAQUS建立了有限元分析模型,考察了既有材料本构模型对该类短柱的适用性。Axial compression test was carried out on eight innovative concrete-filled stainless-steel tubular(CFSST)stub columns to analyze the effects of new constructional materials,namely inew stainless steel and concrete made with waste materials and by-products,on the post-fire behavior of the CFST stub columns,by investigating the mechanical properties such as failure modes,load-strain curves,ultimate strength,ductility and stiffness.The test results indicated that two materials had no obvious influence on the failure modes of CFST columns.The decrement in stiffness and ultimate strength while growth in ductility were also checked.Compared to CFST columns using carbon steel and normal concrete,the new stainless steel,as well as waste material concretes,had positive effect on the strength reduction of composite columns after elevated temperatures.By introducing the reduction factor of materials,it was found that Chinese code DBJ-T13-51—2020 could predict the residual strength of this CFST columns with green materials in good agreement.Finally,the finite element(FE)models were established by using ABAQUS to check the feasibility of current material models to simulate the structural response.

关 键 词：不锈钢管混凝土(CFSST) 高温后 轴压性能 不锈钢 固废混凝土 

分 类 号：TU43[建筑科学—岩土工程]