Which statement best describes the role of yielding zones in seismic detailing?

• A. Energy is dissipated only through damping devices added to the structure.
• B. Damping devices govern all energy dissipation with no yielding.
• C. Yielding zones in detailing act as energy-dissipation mechanisms during seismic events.
• D. Seismic detailing has no influence on energy absorption.

Answer: (C)

Yielding zones are places in a structure where controlled inelastic deformation occurs during strong shaking to absorb seismic energy. By design, specific members form plastic hinges and yield, creating hysteretic energy dissipation as the members slide through their elastic–plastic range. This ductile behavior lowers the forces transmitted to the rest of the structure and limits damage to non-ductile elements, while keeping overall stability and protecting lives.

Damping devices can contribute to energy dissipation, but they are not the sole path for energy loss. Relying only on damping devices ignores the principal mechanism of energy absorption in a ductile frame, which is the inelastic deformation concentrated in the yielding zones. Conversely, stating that seismic detailing has no influence on energy absorption misses the purpose of detailing, which is to control where and how energy is dissipated.

So the best description is that yielding zones in detailing act as energy-dissipation mechanisms during seismic events.