冻融循环环境下方钢管混凝土粘结强度试验研究  

STUDY ON THE BOND STRENGTH OF CONCRETE FILLED SQUARE STEEL TUBES UNDER FREEZE-THAW CYCLES ENVIORONMENT

作　　者：李俊华 王维宸[2] 周春恒 陈志辉 LI Jun-hua;WANG Wei-chen;ZHOU Chun-heng;CHEN Zhi-hui(School of Civil Engineering,Quanzhou Institute of Information Engineering,Quanzhou,Fujian 362000,China;School of Civil&Environmental Engineering and Geography Science,Ningbo University,Ningbo,Zhejiang 315211,China)

机构地区：[1]泉州信息工程学院土木工程学院,福建泉州362000 [2]宁波大学土木工程与地理环境学院,浙江宁波315211

出　　处：《工程力学》2024年第S01期206-214,共9页Engineering Mechanics

基　　金：国家自然科学基金项目(51978344)。

摘　　要：为研究冻融循环环境下方钢管混凝土的粘结性能,设计制作了19组57个方钢管混凝土短柱试件,并对这些试件开展冻融循环后的推出试验。获得了试件的荷载-滑移曲线,分析方钢管混凝土粘结力的组成以及冻融循环次数、构件长细比、钢管宽厚比对粘结强度的影响。试验结果表明,冻融循环后方钢管混凝土的荷载-滑移曲线与常温下总体相似,包含无滑移段、上升段、下降段、残余段。无滑移段的粘结作用由化学胶结力提供,滑移产生后的粘结作用由摩擦力和机械咬合力提供。在试验参数范围内,方钢管混凝土的粘结强度随着冻融循环作用次数增加呈幂函数减小,随着构件长细比的增大呈线性降低,随着钢管宽厚比的增大呈指数下降。在试验结果基础上,提出了冻融循环后方钢管混凝土粘结强度的计算公式,计算结果与试验结果总体总体吻合。In order to study the bond performance of concrete-filled steel tubes under freeze-thaw cycling environment,19 groups of 57 concrete-filled square steel tubular short column specimens were designed and manufactured,and the push out tests were carried out on these specimens after freeze-thaw cycle.The load slip curves of the specimens were obtained.The composition of the bond force of concrete-filled square steel tubes and the effects of the number of freeze-thaw cycles,the slenderness ratio of members and the width thickness ratio of steel tube on the bond strength were analyzed.The test results show that the load slip curve of CFST after freeze-thaw cycle is generally similar to that at room temperature,including non-slip section,rising section,falling section and residual section.The bonding action in the non-slip stage is provided by the chemical bonding force,and the bonding action after slip is provided by the friction and mechanical biting force.Under the condition of test parameters,the bond strength of concrete-filled square steel tubes decreases in a power function with the increase of the number of freeze-thaw cycles,decreases linearly with the increase of the slenderness ratio of the member,and decreases exponentially with the increase of the width thickness ratio of the steel tube.Based on the test results,the calculation formula of bond strength of concrete-filled steel tubes after freeze-thaw cycle is proposed,with the calculation results generally consistent with the test results.

关 键 词：钢管混凝土 冻融循环 推出试验 粘结强度 粘结退化 

分 类 号：TU398.9[建筑科学—结构工程]