Seismic performance analysis and evaluation for low-ductile RC frame structures

The factors that have influences on the seismic performance of low-ductile structures with poor seismic fortification level, insufficient seismic fortification measures and long service ages were summarized. The sensitivity analysis of these factors was conducted at component level. Two RC frame structures with same dimension and reinforcement ratio but different ductility were modeled and analyzed using OpenSees, and the differences of their seismic performance and failure modes were evaluated. The results show that seismic force-resisting capacities of long low-ductile structures are weaker than those of newly-built ones, but all can satisfy the current seismic code under severe earthquakes. When structures suffer severer earthquake, seismic capabilities of these structures are much weaker than those of newly-built ones, showing low ductility, poor energy dissipation capacities, weak collapse-resistance capacities, and brittle failure modes.