NONLINEAR ANALYSIS OF FRP- REINFORCED CONCRETE SLABS WITH A SHEAR-LOCKING FREE LAYERED COMPOSITE PLATE ELEMENT

Fibre reinforced polymers (FRPs) have made significant progress in replacing the conventional steel bars as an alternative reinforcement for concrete members in special situations in the last decade. In this study, a unique shear-locking free rectangular composite layered plate clement is proposed based on Mindlin-Reissner plate theory and Timonshenko's composite beam functions for nonlinear finite clement analysis of fibre reinforced plastic (FRP)-reinforced concrete slabs. The plane displacement interpolation functions of a quadrilateral isoparametric element with drilling degrees of freedom are employed to describe the membrane effects and the bending effects of the plate elements are represented by the deflection and rotation functions derived from Timoshenko's composite beam functions. Both geometric nonlinearity and material nonlinearity of the materials, which incorporates tension, compression, tension stiffening and cracking of the concrete, are included in the element model. The developed rectangular composite layered plate element and nonlinear finite clement analysis procedures are validated by comparing the computed results with experimental data of a clamped two-way FRP-reinforced concrete slab under a concentrated load.