Axial Restraint in Diagonally Reinforced Concrete Coupling Beams: An Analytical Investigation

The energy dissipation characteristics of diagonally reinforced concrete coupling beams in coupled core wall lateral force resisting systems is investigated through finite element analysis where the axial restraint due to the wall piers and/or the presence of a floor slab is included. A mesh density analysis is performed to ensure acceptable accuracy of the finite element solution. Furthermore, the modeling technique is validated using experimental results obtained through previous research on reinforced concrete beams with complex geometry. Finally, a finite element model is created based on experimental research on diagonally reinforced concrete coupling beams carried out at the University of Cincinnati. The finite element model is analyzed first with no axial restraint, then with full axial restraint in order to draw conclusions as to the influence of axial restraint on the energy dissipation characteristics of the diagonally reinforced concrete coupling beam lateral force resisting system. It is expected that the restrained structure will offer larger compressive strength and better post-peak behavior than the unrestrained one.