INTERFACE STRESS REDISTRIBUTION IN FRP-STRENGTHENED REINFORCED CONCRETE BEAMS USING A THREE-PARAMETER VISCOELASTIC FOUNDATION MODEL

摘要

In this study, a novel three-parameter viscoelastic foundation model has been developed to predict the long-term behaviors of FRP-strengthened reinforced concrete beams. Both the FRP plate and the RC beam are modeled as Timoshenko's beams connected through the adhesive layer, which is modeled as a three-parameter viscoelastic foundation using Standard Linear Solid model. Closed-form expressions of the time-dependent interface stresses and deflection of the beam are obtained using Laplace transform. The validation of this viscoelastic solution is verified by finite element analysis using a subroutine UMAT based on the Standard Linear Solid model.