Damage reports after recent earthquakes proves that slippage between steel reinforcing bars and the surrounding concrete is one the common causes of damage and collapse of existing RC building structures. The bond-slip mechanism assumes particular importance in RC building structures built until the 70’s, with plain reinforcing bars, previously to the enforcement of modern seismic codes. This type of structures is usually FKDUDFWHUL]HGE\SRRUUHLQIRUFHPHQWGHWDLOLQJSRRUERQGSURSHUWLHVDQGLQDGHTXDWHFRQFUHWHFRQ¿QHPHQW,Q5&EXLOGLQJVVXEMHFWHGWRF\FOLF ORDGVDVWKHLQGXFHGE\HDUWKTXDNHVKLJKVWUHVVFRQFHQWUDWLRQRFFXUVDWWKHEHDPFROXPQMRLQWVPDNLQJWKLVUHJLRQVSURQHWRWKHRFFXUUHQFH RIVHYHUHGDPDJH%HDPFROXPQMRLQWVDUHSDUWLFXODUO\VHQVLWLYHWRWKHERQGVOLSPHFKDQLVPGXHWRWKHVWUHVVFRQFHQWUDWLRQEXWDOVRGXHWRWKH IDFWWKDWDQFKRUDJHRIEHDPDQGFROXPQORQJLWXGLQDOUHLQIRUFLQJEDUVLVW\SLFDOO\PDGHLQWKHMRLQWYLFLQLW\
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Comparative analysis of the cyclic behaviour of
beam-column joints with plain and deformed reinforcing bars
Análise comparativa do comportamento cíclico
de nós viga-pilar com armadura lisa e nervurada
C. FERNANDES a cfernandes@ua.pt
J. MELO b MRVHPHOR#XDSW
H. VARUM c hvarum@ua.pt
A. COSTA d agc@ua.pt
Abstract
Resumo
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a University of Aveiro, Civil Engineering Department, cfernandes@ua.pt, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal; b University of Aveiro, Civil Engineering Department, josemelo@ua.pt, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal; c University of Aveiro, Civil Engineering Department, hvarum@ua.pt, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal; d University of Aveiro, Civil Engineering Department, agc@ua.pt, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
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Comparative analysis of the cyclic behaviour of beam-column joints with plain and deformed reinforcing bars
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