Mechanism of improving ductility of high strength concrete T-section beam confined by CFRP sheet subjected to flexural loading
来源期刊：中南大学学报(英文版)2013年第1期
论文作者：WANG Su-yan(王苏岩) WANG Ze-yuan(王泽源)
文章页码：246 - 255
Key words：high strength concrete; fiber reinforced polymer; T-section; beam; ductility; plastic hinge
Abstract: For the purpose of inventing a new seismic retrofitting method for the reinforced high strength concrete (HSC) T-section beam using carbon fiber reinforced polymer (CFRP) sheet, three series, a total of twelve T-section beams with nine specimens confined by CFRP sheet in the plastic zone and three control beams were conducted up to failure under four-point bending test. The effectiveness of confining CFRP sheet on improving the flexural ductility of unstrengthened T-section beams was studied. The parameters such as the width and the thickness of CFRP sheet and the type of T-section were analyzed. The experimental results show that ductility and rotation capacity of plastic hinge can be improved by the confinement of CFRP sheet, and the ductility indices increase with the increment of width and thickness of CFRP sheet. A plastic rotation model considering the width of CFRP sheet and the effect of flange of T-section beam is proposed on the basis of the model of BAKER, and the test results show a good agreement with the perdicted results. The relevant construction suggestions for seismic retrofitting design of beam-slabs system in cast-in-place framework structure are presented.
WANG Su-yan(王苏岩)1, WANG Ze-yuan(王泽源) 2
(1. Faculty of Infrastructure Engineering, Dalian University of Technology, Dalian 116024, China;
2. The IT Electronics Eleventh Design & Research Institute Scientific and Technological
Engineering Corporation Limited Dalian Office, Dalian 116600, China)
Abstract:For the purpose of inventing a new seismic retrofitting method for the reinforced high strength concrete (HSC) T-section beam using carbon fiber reinforced polymer (CFRP) sheet, three series, a total of twelve T-section beams with nine specimens confined by CFRP sheet in the plastic zone and three control beams were conducted up to failure under four-point bending test. The effectiveness of confining CFRP sheet on improving the flexural ductility of unstrengthened T-section beams was studied. The parameters such as the width and the thickness of CFRP sheet and the type of T-section were analyzed. The experimental results show that ductility and rotation capacity of plastic hinge can be improved by the confinement of CFRP sheet, and the ductility indices increase with the increment of width and thickness of CFRP sheet. A plastic rotation model considering the width of CFRP sheet and the effect of flange of T-section beam is proposed on the basis of the model of BAKER, and the test results show a good agreement with the perdicted results. The relevant construction suggestions for seismic retrofitting design of beam-slabs system in cast-in-place framework structure are presented.
Key words:high strength concrete; fiber reinforced polymer; T-section; beam; ductility; plastic hinge
