摘要
精确的材料本构模型是实现结构直接分析的前提,但目前尚无适用于椭圆钢管混凝土结构直接分析法的材料本构关系模型。基于课题组前期试验,分析了椭圆钢管混凝土柱中钢材和混凝土的纵向应力-应变关系的发展规律。根据钢管双向受力和核心混凝土三向受力的特点,考虑截面长短轴比的影响,提出了椭圆钢管混凝土柱中钢管和混凝土的纵向应力-应变关系模型。依照静力平衡条件和变形协调条件,采用提出的钢管和混凝土应力-应变关系模型计算了椭圆钢管混凝土柱的荷载-变形全过程关系曲线。分析得到的理论荷载-位移曲线与试验结果吻合良好,计算得到的承载力与试验值、规范GB 50936—2014和EC4的计算值也吻合较好,验证了提出的椭圆钢管混凝土中钢管和混凝土应力-应变关系模型的准确性,为基于直接分析法的椭圆钢管混凝土结构的设计提供了依据。
The accurate material constitutive model is the premise of realizing direct analysis method of structures,but the model for elliptical concrete-filled steel tube(CFST)structures has not been proposed yet.According to previous experiments of the research group,the development laws of the longitudinal stress-strain curves of steel tube and concrete in elliptical CFST columns were studied in this paper.Based on the characteristics of biaxial stress of steel tube and triaxial stress of core concrete,the longitudinal stress-strain models of steel tube and core concrete considering the effect of aspect ratio were suggested,respectively.Furthermore,on the basis of the proposed stress-strain relationships of steel tube and concrete,the load-deformation curves of the elliptical CFST column were established according to the static equilibrium condition and deformation compatibility condition.The theoretical load-displacement curves are verified well with test results.Also,axial compressive capacities of elliptical CFST columns are similar to experimental values and calculated values according to specifications GB 50936—2014 and EC4.The constitutive models of elliptical steel tube and concrete proposed in this paper are proved to be accurate,which can recommend for the structural design of elliptical CFST structures based on the direct analysis method.
作者
王凤芹
刘发起
杨华
WANG Fengqin;LIU Faqi;YANG Hua(School of Civil Engineering,Harbin Institute of Technology,Harbin 150090,China;Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education,Harbin Institute of Technology,Harbin 150090,China)
出处
《建筑结构学报》
EI
CAS
CSCD
北大核心
2021年第S02期332-338,共7页
Journal of Building Structures
基金
国家自然科学基金项目(51978209)
关键词
椭圆钢管混凝土柱
直接分析法
纵向应力-应变关系
荷载-位移曲线
轴压承载力
elliptical concrete-filled steel tubular column
direct analysis method
longitudinal stress-strain relationship
load-displacement curve
axial compressive capacity
