Seismic retrofit of a structure using self-centring precast concrete frames with enlarged beam ends. Issue 22 (19th November 2020)

• Record Type: Journal Article
• Authors: Nour Eldin, Mohamed; Naeem, Asad; Kim, Jinkoo
• Is Part Of: Magazine of concrete research. Volume 72:Issue 22(2020)
• Page Start: 1155
• Page End: 1170
• Publication Date: 2020-11-19
• Subjects: precast concrete -- structural analysis -- structural design; Concrete -- Periodicals; Concrete construction -- Periodicals; Concrete -- Testing -- Periodicals; 624.1834
• DOI: 10.1680/jmacr.19.00012
• Languages: English
• ISSNs: 0024-9831

Abstract

Abstract : This research proposes a procedure to retrofit existing structures using self-centring post-tensioned precast concrete (SC-PC) frames. The procedure utilises the initial stiffness of the un-retrofitted structure and predicts the required initial stiffness of the retrofitted one using the N2 method. A modified precast beam-end shape is proposed to double the re-centring moment capacity of the retrofit frame at the beam–column interface. Different retrofit cases for two- and three-dimensional structures utilising the proposed and conventional PC beams are investigated. The results of the proposed procedure are verified through non-linear time history analysis using two different sets of earthquake records compatible with the design-level response spectrum. The study results reveal that the SC-PC retrofit frames are quite effective in controlling the earthquake-induced storey drift of the retrofitted structures while eliminating the residual storey drift. The results also indicate the effectiveness of the proposed beam shape in mitigating the inter-storey drift demand of the analysis model structures.