单轴对称十字型钢混凝土柱轴压荷载-变形曲线理论模型及其试验验证  

Theoretical model and experimental verification of load-deformation curve of steel reinforced concrete columns with monosymmetric cross-shaped steel

作　　者：余吉鹏 周天华[1] 李亚鹏 张钰 YU Jipeng;ZHOU Tianhua;LI Yapeng;ZHANG Yu(School of Civil Engineering,Chang'an University,Xi'an 710061,China)

机构地区：[1]长安大学建筑工程学院,陕西西安710061

出　　处：《中南大学学报（自然科学版）》2021年第5期1621-1633,共13页Journal of Central South University:Science and Technology

基　　金：陕西省重点研发计划项目(2019SF-239)。

摘　　要：为建立单轴对称十字型钢混凝土柱(SRCC-MCS)轴压荷载-变形曲线理论模型,根据箍筋和型钢的约束范围,划分SRCC-MCS截面约束区,借鉴Mander约束混凝土应力-应变关系,建立各约束区混凝土本构模型,基于静力平衡及变形协调,得到SRCC-MCS轴压荷载-变形曲线理论模型和简化模型。对1个十字型钢混凝土柱(SRCC-CS)试件及8个SRCC-MCS试件进行轴心受压试验,从试件破坏模式、荷载-应变曲线和荷载-变形曲线等方面揭示SRCC-MCS轴压受力机理。研究结果表明:SRCC-MCS试件破坏不均匀,偏心H型钢对侧混凝土压溃剥落较为严重;十字型钢偏心率和箍筋间距提高对SRCC-MCS轴压性能产生不利影响;混凝土立方体抗压强度上升,SRCC-MCS轴压承载力上升,变形能力下降;配钢率增加,SRCC-MCS轴压承载力和变形能力上升;采用理论模型和简化模型计算的荷载-变形曲线与试验曲线吻合较好。To establish the theoretical model of load-deformation curve of steel reinforced concrete columns with monosymmetric cross-shaped steel(SRCC-MCS),the confined areas of SRCC-MCS were divided according to scoping constraints of profile steel and stirrups.Based on Mander's stress-strain model of confined concrete,the constitutive models for each confined areas of concrete were proposed.Based on static balance and deformation coordination,the theoretical model and simplified model of load−deformation curve were established.Eight SRCC-MCSs and a steel reinforced concrete column with cross−shaped steel(SRCC-CS)were carried out under pure compression.The axial load bearing mechanism of the specimens was investigated according to the failure mode,load−strain curves and load-deformation curves.The results show that the failure of SRCC-MCS specimens are uneven,and concrete crushing and spalling for SRCC-MCS specimens away from the eccentric H-shaped steel are more severe.With the increase of the cross shaped steel eccentricity ratio and hoop spacing,they have negative impact on the axial compression performance of SRCC-MCS.Increasing the cubic concrete compressive strength enhances axial capacity of SRCC-MCS,but decreases their deformability.The axial capacity and the deformability of SRCC-MCS increases with the steel ratio.The load−deformation curves calculated by the theoretical model and simplified model coincide with the test curves.

关 键 词：型钢混凝土柱 约束机制 非对称型钢 应力-应变模型 试验验证 

分 类 号：TU398[建筑科学—结构工程]