Torsional Analysis of Perforated Core Structure

A simple method for torsional analysis of perforated core wall structures considering shear deformation is presented. The governing differential equation is derived from compatibility using open section thin-wall torsion-bending theory. The method is compared with conventional analysis in which shearing strains are ignored to show that for a narrow band of openings or stiff connecting beams the conventional analysis overestimates the rotational stiffness of the core wall assembly. This is also borne out by the experimental evidence. Since the governing differential equation has the same form as that of the conventional solution, existing tables and graphs can be used to obtain the deformations and internal forces.