FORMULATION MECHANISM AND MECHANICAL PERFORMANCE OF FUNCTIONALLY GRADED FLEXURAL CONCRETE MEMBERS

Based on a theoretical analysis, a new functionally graded flexural concrete member (FGFCM) is proposed. Through the combined reinforcement of graded FRP bars and steel bars, the distribution gradient of the flexural load-bearing capacity along the member is adapted to the load distribution gradient. Then multiple functionally graded segments in the FGFCMs reach their plastic state, and the functional gradient is formed to more utilize the seismic capacity of the members. The distribution and development degree of the plasticity in the FGFCMs can be effectively controlled to achieve the ductile failure mode and better recoverability. The functional gradient greatly improves the deformation capacity, increases the lateral bearing capacity, reduces the ultimate stiffness, and enhances the seismic performance of the members. The model experiment proved the feasibility of the FGFCMs and their mechanical effects, and verified the effectiveness and engineering practicability of the proposed construction scheme to form the functional gradient.