Reliability under Seismic Loads of RC Structures Strengthened with FRP using Polynomial Dimensional Decomposition approximation
Résumé
The present study aims to estimate effectiveness of applying FRP strengthening in order to enhance the seismic structural reliability of RC frames. Two FRP strengthening configurations were compared: applying flexural FRP strengthening to members – beams/columns – of the RC frame and applying FRP confinement to columns of the frame. Seismic reliability was expressed in term of fragility estimates which involves performing nonlinear time history analysis recoding the maximum lateral top drift as a dynamic demand. A nonlinear time history analysis was carried out using finite elements method FEM. In order to reduce the computational effort, an efficient meta-modeling using Polynomial Dimensional Decomposition PDD in conjunction with the Monte-Carlo Simulation (MCS) was used. In addition, a sensitivity analysis using Sobol indices and Morris screening method were applied to evaluate importance of each random variables considered in the analysis . The proposed approach was applied to a typical three-story RC frame. Numerical results demonstrate the efficiency and computational advantages of the proposed meta-model using PDD for the seismic reliability assessment of structures. Furthermore, it was found that enhancement in seismic reliability corresponds to flexural type is quite higher than that corresponds to confining type.