局部锈蚀圆钢管混凝土短柱轴压承载力试验研究  

Experimental studies on axial compressive bearing capacity of circular CFST stub columns with localized corrosion

作　　者：陈梦成[1,2] 罗苏昌 黄宏[1,2] 方苇[1,2] 许开成[1,2] 钱文磊 CHEN Mengcheng;LUO Suchang;HUANG Hong;FANG Wei;XU Kaicheng;QIAN Wenlei(State Key Laboratory of Service-Performance Monitoring and Protecting for Rail Transit Infrastructures,East China Jiaotong University,Nanchang 330013,China;School of Civil Engineering and Architecture,East China Jiaotong University,Nanchang 330013,China)

机构地区：[1]华东交通大学省部共建轨道交通基础设施性能监测与保障国家重点实验室,江西南昌330013 [2]华东交通大学土木工程建筑学院,江西南昌330013

出　　处：《中南大学学报（自然科学版）》2024年第1期317-329,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(52278180,51878275)。

摘　　要：钢管混凝土(CFST)在服役环境中被腐蚀,导致其钢结构承载力降低,严重威胁到结构的服役性能和使用寿命。首先,采用机加工车铣方法制作模拟局部锈蚀的人工缺陷,然后以钢管外表面局部环向贯通锈蚀位置、锈蚀钢管体积损失率、锈蚀外表面面积损失率(简称锈蚀面积损失率,下同)为试验参数,对45根局部锈蚀圆CFST短柱试件进行轴压承载力试验;其次,分析锈蚀位置、锈蚀钢管体积损失率、面积损失率和壁厚损失率对锈蚀试件承载力、刚度和延性的影响,揭示锈蚀CFST试件破坏机理和承载力退化机制;最后,针对局部锈蚀圆CFST短柱构件轴压承载力提出一个简化实用计算公式。研究结果表明:各试件具有类似的破坏特征,主要呈明显的腰鼓状破坏,且发生在锈蚀区;随着锈蚀钢管体积损失率增大,锈蚀CFST柱的承载力、刚度和延性均出现不同程度的降低;在锈蚀钢管体积损失率和面积损失率相同的情况下,就局部锈蚀位置影响而言,中部影响最大;就锈蚀程度表征参数影响而言,锈蚀钢管体积损失率影响最大,面积损失率次之,壁厚损失率最小;本文提出的简化实用公式可为圆钢管混凝土构件全寿命设计提供参考依据。During the service period,the load bearing capacity of concrete filled steel tubular(CFST)structures decreases over time under corrosive environment,seriously threatening the service performance and service life of the structures.Firstly,a turn milling machining method was used to manufacture an artificial defect to simulate a localized through-circumferential corrosion on the outer surface of steel tube.After this,axial compression load bearing capacity experiments were conducted on 45 circular CFST stub columns with localized through-circumferential corrosion by varying the corrosion position,volume loss ratio and external surface area loss ratio(area loss ratio for short,similarly hereinafter)of corroded steel tube.Secondly,the effects of localized corrosion position,volume loss ratio,area loss ratio and wall-thickness loss ratio on the axial load bearing capacity,stiffness and ductility of locally corroded CFST stub column were discussed,and the failure and load bearing capacity degradation mechanisms of the corroded specimens were revealed.Finally,a simplified practical calculation formula was established for the axial bearing capacity of CFST stub columns with localized corrosion.The results show that the corroded specimens have similar responses.Obvious outward bulging failure is predominated and occurs in the corrosion region.With increasing corrosion volume loss ratio,the bearing capacity,stiffness and ductility of the specimen with localized corrosion decrease at different level.Given the same corrosion volume loss ratio and area loss ratio,as for the impact of localized corrosion position,the largest impact appears in the specimen with localized through-circumferential corrosion at its mid-part;as for the effect of corrosion level indexes,the largest impact is that of volume loss ratio,followed by that of area loss ratio,and the minimum impact is that of wall-thickness loss ratio.The proposed prediction model can provide a reference framework for the life-cycle design of CFST columns.

关 键 词：圆钢管混凝土短柱 局部锈蚀 轴压承载力 退化机制 

分 类 号：TU938.9[建筑科学—结构工程]