After Chi-Chi earthquake in 1999 Taiwan National Center for Research on Earthquake Engineering started to conduct a series of research and experiments for the seismic assessment and retrofit techniques of existing building With development of new concrete materials application of high strength concrete (HSC) is effective to reduce the usage of material and the weight of the structure However HSC showed brittle behavior and dramatic drop of strength after member cracking Ultra-high performance fiber reinforced concrete (UHPFRC) was used to retrofit reinforced concrete beam-column joints (BCJs) in this study Dimensions of member section can be decreased after retrofitting by increasing concrete compressive strength Furthermore addition of steel fiber in the concrete increased tensile strength and ability of energy dissaption due to fiber bridging effect According to the typical substandard reinforcing detail in old existing building a non-ductile reinforced concrete exterior BCJ was designed as control specimen Six different retrofitting solutions were applied to investigate the effectiveness of UHPFRC for retrofitting existing BCJs In addition to retrofitting existing BCJs two BCJs which experienced complete damaged retrofitted by UHPFRC and steel mesh were included in this study Due to the test result the applictation of UHPFRC to retrofit existing and damaged BCJs showed significant effectiveness UHPFRC jacket provided a considerable increase in strength by 35%~66% and ability of energy dissipation by 35%~217% Damaged index can be also reduced after retrofitting
Date of Award | 2020 |
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Original language | English |
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Supervisor | Chung-Chan Hung (Supervisor) |
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Effectiveness of Ultra-High Performance Fiber Reinforced Concrete for Retrofitting Beam-Column Joints
信睿, 蕭. (Author). 2020
Student thesis: Doctoral Thesis