Immediate Operation at Maximum Credible Event

Police, fire and emergency response call centers, community meeting rooms and department offices are housed in the Salt Lake City Public Safety Building. Salt Lake City, a risk-averse and well-informed client, envisioned an enduring facility that would provide the structural performance needed to withstand the Maximum Credible Earthquake (MCE) with a return period of approximately 2,500 years. The City expected this facility to meet immediate occupancy performance criteria for this level of shaking, exceeding code minimum for an essential services facility which only required Life Safety during an MCE. Holmes joined the project team as special seismic consultant to devise the lateral-force-resisting system, bringing performance-based engineering expertise to earthquake country.

The City envisioned an enduring facility that would withstand a Maximum Credible Earthquake.

Holmes utilized performance-based engineering to explore a number of different protective seismic systems that also gave consideration to progressive collapse-blast resistance and contents protection. The specific systems tested include base isolation, damped steel and concrete moment frames, and dual-systems incorporating rocking shear walls with perimeter moment frames.

The client selected the damped steel moment frame, the second best performer, because it was adaptable to the architectural program which sought to balance the needs of an emergency services center with an open and inviting environment. The Salt Lake City Public Safety Building utilized an isolated floor system in a localized area to provide additional seismic protection to sensitive server and electronic equipment.