NUMERICAL SIMULATIONS ON STRENGTHENED STRUCTURES WITH HYBRID FIBER SHEETS

摘要

In this paper, a special emphasis is placed on how to numerically simulate the overall behavior of the structures strengthened by hybrid fiber sheets including progressive rupture and different failure modes. Based on the experimental observations from the uniaxial tension test of hybrid fiber sheets, a macro-mechanical damage constitutive model is developed to simulate the stress transfer mechanism caused by progressive rupture of higher modulus type in the hybrid fiber sheets. It is then implemented into a general-purpose finite element program using a user-defined material subroutine to simulate the behaviors of hybrid fiber sheets loaded in tension and the hybrid FRP-strengthened RC beams, which are compared with the corresponding experimental data. In addition, some discussion are made on the factors influencing the load drops in the hybrid effect.