ELASTO-PLASTIC ANALYSIS OF CORE STRUCTURES SUBJECTED TO TORSION.

Based on the continuum approach, an analysis is presented for the elasto-plastic behavior of torsionally loaded shear cores consisting of open box structures braced by lintel beams at each floor level. Assuming a plastic hinge concept and a bilinear moment-rotation relationship for the connecting beams, the analysis enables the spread of plasticity to be traced throughout the loading process from working to ultimate load. For any specified practical limiting value of the ductility factor, the maximum permissible applied torque, the amount of beam plastic rotation required at each story level in the plastified zone, and the corresponding stresses and deformations throughout the structure may be evaluated.