钢管预置集料混凝土中长柱受压性能试验  

Experiment on compression performance of preplaced aggregate concrete-filled steel tube slender column

作　　者：吕晶[1] 郑健龙 韩文超 张金翼 赵欢 LÜJing;ZHENG Jianong;HAN Wenchao;ZHANG Jinyi;ZHAO Huan(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）》2024年第6期2247-2259,共13页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(51908046);陕西省重点研发计划项目(2023-YBSF-219);中国博士后基金资助项目(2019M653517);长安大学中央高校基本科研业务费专项资金资助项目(300102281204)。

摘　　要：为了探究钢管预置集料混凝土中长柱受压性能,首先,考虑混凝土类型、混凝土强度、径厚比、长径比和偏心率等参数影响,设计了11根钢管预置集料混凝土中长柱和3根普通钢管混凝土中长柱;其次,通过轴压和偏压试验,并结合有限元分析法,研究了试件破坏形态、承载力、变形特征等变化规律;最后,基于极限平衡理论,提出了适用于钢管预置集料混凝土中长柱轴压与偏压承载力计算公式。研究结果表明:钢管预置集料混凝土中长柱破坏形态与普通钢管混凝土中长柱的破坏形态相似,均为弯曲失稳破坏;钢管预置集料混凝土中长柱承载能力与普通钢管混凝土中长柱承载能力相当,但钢管预置集料混凝土试件轴向刚度是普通钢管混凝土试件轴向刚度的1.2倍左右,表现出良好的抗变形能力;钢管预置集料混凝土中长柱径厚比由39.75降低至19.88,承载能力提高33.8%;长径比由6增大至15时,承载能力降低20.5%;偏心率由0.25增大至1.0时,承载力降低49.5%;钢管预置集料混凝土中长柱稳定系数受混凝土强度和径厚比影响较小,但随着长径比和偏心率增大而近乎呈线性降低趋势。本文提出的承载力计算公式可为钢管预置集料混凝土中长柱设计提供参考。In order to explore the compression performance of preplaced aggregate concrete-filled steel tube(PACFST)slender column,firstly,11 PACFST slender columns and 3 normal concrete-filled steel tube(CFST)slender columns were designed with consideration of influential factors such as concrete type,concrete strength,diameter-to-thickness ratio,length-to-diameter ratio and eccentricity ratio.Secondly,by the axial compression and eccentric compression tests and the finite element analysis method,the variation law of failure mode,bearing capacity and deformation characteristics of the specimens were studied.Finally,based on the limit equilibrium theory,the calculation equations for axial compression and eccentric compression bearing capacity of PACFST slender columns were established.The results show that the failure modes of PACFST slender columns are similar to those of CFST slender columns,both of which are flexural buckling failure.The bearing capacity of PACFST slender columns is equivalent to that of CFST slender columns,but the axial stiffness of PACFST slender columns is about 1.2 times of that of CFST slender columns,which shows a good ability to resist deformation.The bearing capacity increases by 33.8%when the diameter-to-thickness ratio of PACFST slender columns decreases from 39.75 to 19.88.The bearing capacity drops by 20.5%as the length-to-diameter ratio increases from 6 to 15.The bearing capacity decreases by 49.5%when the eccentricity ratio increases from 0.25 to 1.0.The stability coefficient of PACFST slender columns is affected by concrete strength and diameter-to-thickness ratio slightly,but decreases almost linearly with the increase of length-to-diameter ratio and eccentricity ratio.The calculation formula of bearing capacity proposed in this paper can provide reference for the design of PACFST slender columns.

关 键 词：钢管混凝土 预置集料混凝土 中长柱 受压性能 承载力计算方法 

分 类 号：TU398.9[建筑科学—结构工程]