（1 兰州交通大学道桥工程灾害防治技术国家地方联合工程实验室， 兰州 730070； 2 甘肃恒路交通勘察设计院有限公司， 兰州 730070；  3 中铁二十一局集团有限公司， 兰州 730070）

［摘要］为了得到核心混凝土缺陷率与缺陷位置对钢管混凝土构件承载力的影响规律，进行了27根不同缺陷率与缺陷位置的钢管混凝土构件承载力试验。试验分析结果得出：缺陷率相同的条件下，中心位置缺陷时，钢管混凝土构件承载力损失较小，管壁侧位置缺陷时，钢管混凝土构件承载力损失较大； 缺陷率为5%时，中心位置缺陷试件较无缺陷试件承载力损失14%，管壁侧缺陷试件较无缺陷试件承载力损失0%； 缺陷率为20%时，中心位置缺陷试件较无缺陷试件承载力损失35%，管壁侧位置缺陷试件较无缺陷试件承载力损失59%； 缺陷位置相同时，缺陷率越大其承载力损失越大，弹塑性阶段的历程越短； 内部缺陷对钢管混凝土构件承载力影响较大，工程中应严格控制钢管混凝土构件的内部缺陷。

［关键词］钢管混凝土； 缺陷率； 缺陷位置； 承载力； 内部缺陷

中图分类号：TU398-7文献标识码：A文章编号：1002-848X(2021)02-0078-07

Influence of defect rate and location of core concrete on the bearing capacity of concrete-filled steel tubular

ZHANG Rongling1, HAO Zhaofeng1, MA Lina1, NING Guixia1, LI Zhiyang2, GAO Fei3

(1 National and Provincial Joint Engineering Laboratory of Road & Bridge Disaster Prevention and Control, Lanzhou Jiaotong University, Lanzhou 730070, China; 2 Traffic Survey and Design Institute of Gansu Henglu Co., Ltd., Lanzhou 730070, China； 3 China Railway 21st Bureau Group Co., Ltd., Lanzhou 730070, China)

Abstract:In order to obtain the influence law of core concrete defect rate and location on the bearing capacity of concrete-filled steel tubular members, 27 concrete-filled steel tubular members with different defect rate and location were tested. The results show that, under the same defect rate, the bearing capacity loss of concrete-filled steel tubular members is smaller when the center location is defective, and the bearing capacity loss of concrete-filled steel tubular members is larger when the side of the pipe wall location is defective. When the defect rate is 5%, the bearing capacity of the defective specimen at the center position is 14% lower than that without defects, and the bearing capacity of the defective specimen at the side of the pipe wall is 20% lower than that without defects. When the defect rate is 20%, the bearing capacity of the defective specimen at the center position is 35% lower than that without defects, and the bearing capacity of the defective specimen at the side of the pipe wall is 59% lower than that without defects. With the same defect location, the larger the failure rate, the greater the bearing capacity loss and the shorter the elastoplastic stage. Internal defects have a great impact on the bearing capacity of concrete-filled steel tubular members, so internal defects of concrete-filled steel tubular members should be strictly controlled in engineering.

Keywords:concrete-filled steel tube; defect rate; defect location; bearing capacity; internal defect

*国家自然科学基金(51768033，52068042)，长江学者和创新团队发展计划滚动支持(IRT_15R29)。

作者简介：张戎令，博士，教授，硕士生导师，Email: mogzrlggg@163.com。