External Confinement with Basalt Fiber Ropes in Existing Reinforced Concrete Structures

Abstract

AbstractExisting reinforced concrete structures designed according to previous generation seismic codes, often suffer from premature, abrupt and detrimental failures in cases of intense earthquakes. In this study the seismic response of an existing building is analytically investigated while taking into account the influence of different detailing of brick wall infills. The assessment is performed with 3D static inelastic (Pushover) or with incremental Dynamic time‐history analyses (IDA) with the SeismoStruct Software. Buildings with inadequate performance receive continuous transverse pre‐tensioned Basalt Fiber Ropes (BFR) as external shear and confining strengthening reinforcement. The inelastic analyses conclude that buildings with short columns suffer from early collapses at low top displacements due to detrimental local shear failure of the above‐mentioned members. Both shear and crush confined concrete related failures of the critical columns are eliminated and overall base shear strength is increased. BFR external wrapping increases the ultimate top building displacements as well. IDA are thoroughly elaborated to assess the collapse mechanism of the structures and conclude ultimate base shear and top displacement values for the critical cases of buildings under investigation.