DUCTILITY CALCULATION OF REINFORCED CONCRETE SHEAR WALLS

As far as the ultimate behavior of the reinforced concrete (RC) shear walls is concerned, it is the ultimate deformation and the ultimate load-bearing capacity that dominate the performance of the walls. Previously, few studies addressed explicitly the deformation capacity of RC shear walls. A rational evaluation of deformation capacity, associated with both elastic and post-elastic responses, is needed to satisfy the specific performance criteria of RC shear walls. In this paper, an attempt has been made to investigate the deformation ductility of RC shear walls under cyclic loading. A calculation method for the deformation ductility ratio of shear walls is established with consideration of the confinement of boundary zones at both ends. The influence of axial compression ratio, shear-span ratio and the characteristic value of stirrup in confined boundary zone on the ductility of the walls are studied. The experimental results of 39 RC shear walls subjected to horizontal cyclic loading with different axial compression ratios are employed to verify the proposed calculation method. Using the method established, factors influencing the deformation ductility of shear walls are studied. It is concluded that to design the shear walls with the expected ductility, the axial compression ratio should be limited and the confined boundary zones must be provided.