STATIC PUSHOVER BEHAVIOUR OF FIXED AND HINGED RCC PORTAL FRAMES

V. G. Kondekar, A. A. Mehta

Abstract: The RCC building frames are usually analyzed, designed and constructed with fixed supports. It is known that the damage to the structures during earthquakes depends on the mass and material of the structure, its type and damping, ductility and energy dissipation capacity. The induced seismic forces can be reduced by enhancing the ductility and the energy dissipation capacity of a structure, lowering probability of its failure or collapse. In this regard, this study aimed at comparing the performances of a fix supported single storey single bay RCC portal frame to that with hinged supports. Two scaled down model portal frames were casted having the same geometrical properties with M20 concrete and Fe 250 reinforcement. The hinges were designed as Mesnager hinges transmitting the thrust and shearing force, and permitting greater rotation. Static Pushover analyses of both these portal frames were performed. The portal was subjected to gravity loading and a continuously increasing lateral load. Their load-displacement responses, rotation capacities and the cracking patterns were observed and recorded. The comparisons showed the improved ductility and energy dissipation capacity of the frame with hinged supports.

Keywords: static pushover, portal frame, hinge, ductility

DOI: https://doi.org/10.15623/ijret.2015.0425039