Developing an energy-dissipating plastic hinge cell for earthquake protection of buildings

Tanışer, Sadun
Capacity design is the prevailing seismic design procedure for ductile frame systems. It permits formation of plastic hinges at the beam ends for dissipating the seismic energy imparted by strong ground motions through inelastic response, hence reducing seismic demand in frame members. These reduced force demands however have a cost: Increased deformations and displacements, and more importantly damage caused by nonlinear deformations which occur at the formed plastic hinges. A replaceable plastic hinge (P-Cell) is developed in this study that is placed at the beam-ends during construction. P-Cell is a metallic internal energy dissipating device whose dimensions fit to the beam dimensions whereas its length along the beam is significantly smaller than the beam depth. P-Cell dissipates energy through cyclic moment-rotation response with rotations exceeding 0.05 radians. Their moment capacity are adjusted to values lower than the end-moment capacity of the connecting beams. Hence, entire nonlinear deformations in the frame system occur at the P-Cells, leaving all other members in the linear elastic range during the earthquake. Seismic performance of P-Cells has been verified by laboratory testing under severe load reversals. Further, a two-story steel frame equipped with P-Cells at the first story beam ends is tested through PsD testing. P-Cells which develop inelastic response during the earthquake can be removed and replaced, accordingly the remaining linear elastic frame restores the deformations. P-Cells can be easily implemented in modular steel and precast concrete frame systems. Their implementation in cast-in-place RC is also straight forward with the provided connection details.
Citation Formats
S. Tanışer, “Developing an energy-dissipating plastic hinge cell for earthquake protection of buildings,” Ph.D. - Doctoral Program, Middle East Technical University, 2024.