Title:
Seismic Strengthening of RC Beam-Column Joints with FRP Systems Applicable from the Exterior of the Building
Author(s):
Ciro Del Vecchio, Marco Di Ludovico, Alberto Balsamo, and Andrea Prota
Publication:
Symposium Paper
Volume:
360
Issue:
Appears on pages(s):
462-473
Keywords:
Reinforced Concrete, Retrofit, existing buildings, rehabilitation, earthquake, shear failure
DOI:
10.14359/51740643
Date:
3/1/2024
Abstract:
Recent seismic events demonstrated the high vulnerability of existing reinforced concrete (RC) buildings. Lack of proper seismic details resulted in significant damage to structural components with many collapses and number of fatalities. The destruction of entire cities shield lights on the need of effective strengthening solutions that can be applicable at metropolitan/regional scale. They should be effective increasing significantly the seismic performance, affordable in the cost, fast to apply and with a low level of disruption to the occupants. This research work presents and discusses the preliminary results of an experimental programme on full-scale RC beam-column joints with reinforcement details typical of the existing buildings in the Mediterranean area. After assessing the response of the as-built specimen under a constant axial load and increasing cyclic displacement, a novel FRP-based strengthening system is presented. It combines the use of a quadriaxial CFRP fabric applied on the joint panel with CFRP spikes installed at the end of the beam and columns to improve the bond. The preliminary results pointed out the effectives of this strengthening solution in avoiding the joint panel shear failure and promoting a more ductile failure mode.
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