Ductility of coupled shear walls
Degree GrantorUniversity of Canterbury
Degree NameDoctor of Philosophy
In this project the strength and behaviour of coupled shear walls subjected to seismic type of lateral load are examined. The sensitivity of shear wall response to changes in relative stiffnesses of beams and walls, and the effects of cracking are studied. Using a finite difference approximation the application of laminar analysis is extended to coupled walls with variation in properties of beams and walls with height, different boundary conditions, different pattern of loading and two or more rows of openings. Theoretical approaches are suggested for the estimation of strength and post-cracking stiffnesses of beams and walls. Using these approaches, with the aid of finite difference approximation of the laminar technique, the history of the shear wall's behaviour is followed by an incremental non-linear elasto-plastic analysis which exposes the ductility requirements of beam and wall hinges and reveals the sequence of their yielding. Two quarter full size seven storey reinforced concrete coupled shear wall models, with differently reinforced coupling beams, have been tested under static reversed cyclic loading to simulate seismic effects. The experiments revealed that carefully designed and detailed shear walls can possess adequate ductility to give the desirable protection against catastrophic ground shaking. The shear wall model with diagonally reinforced beams exhibited superior stiffness, ductility and energy dissipation characteristics. Finally, the significant findings of this investigation have been translated into design recommendations for coupled shear wall structures.