Flexural behavior of end-anchored CFRP strengthened RC beams subjected to combined effects of load and temperature

被引：0
|
作者：
Dong K. [1 ]
Liu L. [1 ]
Yang S. [1 ]
Jing F. [2 ]
Hao A. [3 ]
机构：
[1] Department of Civil Engineering, Ocean University of China, Qingdao
[2] Yantai Maritime Safety Administration, Yantai
[3] Binzhou City Highway Survey and Design Institute, Binzhou
来源：
Jianzhu Jiegou Xuebao/Journal of Building Structures | 2023年 / 44卷 / 03期
关键词：
CFRP reinforcement; end anchorage; flexural behavior; flexural test; RC beam; temperature variation;
D O I：
10.14006/j.jzjgxb.2021.0695
中图分类号：
学科分类号：
摘要：
To study the effect of end anchorage on the structural performance of carbon fiber reinforced polymer (CFRP) strengthened reinforced concrete (RC) beams under high temperatures, the flexural tests of end-anchored CFRP strengthened RC beams under temperature and load were carried out. Different end-anchored measures including external bonding, steel plate anchoring and self-locking anchoring were used to investigate the flexural behavior of the strengthened beams. Compared with the external bonding specimens, the end-anchored measures significantly improve the flexural performance of the strengthened beam at normal temperature or high temperature. Steel plate anchoring can effectively limit CFRP end peeling at normal temperature, where the CFRP utilization rate is increased from 43. 6% to 79. 3%, simultaneously its ultimate load is increased by about 12% . However, the steel plate does not restrict the peeling failure of CFRP when the temperature exceeds 100 ℃ . The bearing capacity of steel plate anchoring specimens is degraded to the unreinforced level, and the maximum CFRP utilization rate during the loading process is only 50. 5% . The self-locking anchoring specimens can limit CFRP peeling at any temperature, and the failure modes are mostly CFRP tensile fracture. The self-locking anchoring specimens maximize the utilization efficiency of CFRP material. The ultimate load at 100 ℃ increases by 22. 7% in comparison with the external bonding specimen, while the ultimate load at 120 ℃ is increased by 10% compared with steel plate anchoring specimens. The bearing capacity degradation coefficient was introduced, and the design formula for the flexural bearing capacity of end anchored CFRP-RC beam under temperature was given, which agreed well with test result. © 2023 Science Press. All rights reserved.
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页码：213 / 222
页数：9
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