ANALYSIS OF PUNCHING SHEAR STRENGTH OF REINFORCED LIGHTWEIGHT CONCRETE FLAT SLAB STRENGTHENED BY GFRP

Abstract

Flat slab structural systems are frequently used in various construction scenarios, such as multistorey buildings, bridges, parking garages, and foundation engineering, for their great economical superiority and ease of construction. The slab-column connection problem may be effectively solved by reducing the weight of RC slabs. The introduction of the reinforced lightweight concrete flat slab is helpful in decreasing the weight of the RC flat slabs which thereby solves the slab column connection problem. Punching shear is a failure mechanism in structural components like slabs and foundations when subjected to concentrated force and it occurs at column support points in flat slabs. FRP system is used, to strengthen LWC slabs subjected to punching shear with some advantages such as corrosion resistance, extraordinary tensile strength, low density, and high strength-to-weight ratio. The influence of GFRP on the punching shear strength of lightweight concrete slabs is examined in this study. Glass fibers possess exceptional characteristics equal to or better than steel in certain forms. Low thermal conductivity, high strength, good electrical insulator, elasticity, incombustible, stiffness, and protection from chemical injury are the distinct properties provided by GFRPs. In this study, numerical analysis of LWC slab strengthening using a GFRP strip was investigated. The difference in punching shear capacity using different orientations, locations, widths and fiber orientations is tested. Evaluations are carried out in terms of punching shear capacity, energy absorption and ductility factor. The numerical analysis found that the strengthened slab improved punching shear capacity as compared to the normal LWC slab. The punching shear strength increases when the strip is placed in the diagonal direction, increasing the number of strips and placing the strip at an offset distance from the loading surface.