Ductility Enhancement by Incorporating Slits on Shear Resisting Frame with Haunched Beams

Earthquake are one of the most devastating disasters the world is facing from decades and constant researches are conducted for providing various solutions to improve the seismic performance by using the idea of ductility and stiffness in appropriate manner. Ductility enhancement is one of the key principles of seismic design. Various techniques are introduced to improve the ductile behaviour of the buildings in past decades. Reduced web sections are one of the older concepts that follows the idea of predetermined failure at determined weak regions. Incorporating slits allows the weakening of slits thus utilizing plastic strain capacity of material which results in dissipating energy and improving ductile ability of structures. This study focuses on improving the ductile behaviour and energy dissipation characteristics of shear resisting frame with haunched beams by using slits at the shear link. Shear resisting frame (SRF) is an innovative concept where failure occurs by shear yielding. SRF is suitable for low span to depth ratio’s where moment resisting frames can’t be used. SRF with haunched beam is used in this study to prevent sudden transition from prismatic beam to link and thus avoiding sudden discontinuity. The parametric study was conducted on the link separately to avoid the computational time and the link with better performance was attached to the frame to analyze the seismic behaviour of the shear resisting frame with haunched beams (SRFH). Effect of aspect ratio of slits, orientation and number of slits on improving the ductile characteristics of the frame were studied. Slits improved the ductile behaviour of the frame by 75% and energy dissipation increased by more than 100%. Rotation capacity of the links were also improved thus improving the over all seismic performance of the frame.