Seismic Analysis of RC Frames with Brick Infill Panel Strengthened by Steel Cage and Expanded Metal

Abstract

The seismic analysis of reinforced concrete infilled frame strengthened by using steel cage and expanded metal was investigated.  The strengthening technique of steel cage consisted of steel angle, batten and expanded metal sheet was employed. The brick infill panel was strengthened with ferrocement and expanded metal. The flexible base foundation was considered by modelling the pile foundation with the lateral and the vertical spring stiffness. Eight types of frames: four existing frames and four retrofit frames were analyzed by nonlinear static analysis and nonlinear time history analysis with 20 ground motion records.  It was found that the initial stiffness and the strength of the retrofit frames were significantly higher than those of the existing frames.  The observed seismic damage of the retrofit frames was decreased to the specified limit.  The initial stiffness of the frames with flexible foundation was lower than that of the fixed base resulting to the larger displacement and the higher seismic damage of the structures.