THE METHOD OF NUMERICAL MODELING FOR EXISTING RC COMPONENTS BASED ON MATERIAL DEGRATION

Based on finite element program ABAQUS，regarding RC multi-age components as research object，the unit C3D8R and unit T3D2 were used to simulate the mechanical behavior of concrete and reinforcement，and the superiority of exponential damping friction model for handling with the problem of contact between corrosion reinforcement and concrete was obviously exhibited，then the Hsich-Ting-Chen strength criterion was taken as concrete failure criterion. The loss of the cross sectional area of reinforcement bars，reduction of the cover and core concrete strength were modified by the single-factor time-dependent corrosion rate. Considering the cracking and spalling in the compressed concrete of compression zone caused by reinforcement corrosion，the modified compressionfield (MCF) was used to predict the time-dependent compressed concrete strength. Finally the modified material constitutive models of corroded reinforcement，concrete and bond-slip were provided. Considering the data of multiage RC component under low frequency cyclic loading，numerical model theory for corroded RC component mentioned above was proved to be reliable，and the achievements can provide a feasible and effective numerical model for the existing RC structures.