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Title: Seismic Response of Concrete Columns Internally Reinforced with GFRP

Author(s): Shamim Sheikh

Publication: Web Session



Appears on pages(s):



Date: 10/29/2020

Corrosion-induced damage in reinforced concrete (RC) structures has raised serious concerns about the safety and economic viability of North American infrastructure. The direct cost of corrosion for highway bridges in the United States is in billions of dollars every year. To address this need for improved durability, noncorrosive glass fiber reinforced polymer (GFRP) bars offer a feasible alternative as reinforcing material. In an extensive research project underway at the University of Toronto, concrete columns reinforced with steel and GFRP are being investigated for their performance under seismic forces. One of recently concluded test series included eight 20 mm diameter columns in which longitudinal reinforcement consisted of steel bars and the transverse reinforced was provided by GFRP spirals. The variables included the amount and spacing of spiral reinforcement, and the level of axial load. The columns were subjected to lateral cyclic displacement excursions while under constant axial load. This paper will present results from this experimental program in the form of moment vs. curvature and shear vs. deflection responses and compare them with the results from previous columns tested in a similar manner. These included square and circular columns with varied section sizes and reinforced with both steel and GFRP. The comparison allowed evaluation of additional variables such as size and shape of column cross section, circular vs. rectilinear confinement, steel vs. GFRP longitudinal and transverse reinforcement. From this experimental and analytical study, it was concluded that the hybrid columns with steel longitudinal reinforcement and GFRP spirals offer a superior non-corrosive alternative to the conventionally reinforced concrete columns for seismic performance, enhanced durability and sustainability.