Unusual Delivery Method Highlights New Long Beach Courthouse Project
Nabih Youssef, principal of structural engineer Nabih Youssef Associates, noted the team’s efforts to meet and, in many cases, exceed the rigorous seismic safety requirements set by the AOC Performance Standards and the California Trial Court Facilities Standards. The facility will have a Seismic Importance Factor of 1.25, Wind Importance Factor of 1.15 and Nonstructural Importance Factor of 1.5.
Inter-story racking displacement was restricted to 1% of story height – just half of that allowed in conventional buildings, Youssef noted. This helps ensure elements like the security doors and elevators remain operational and the exterior envelope of the buildings maintain integrity in the event of a temblor.
Youssef cited the use of moment frames around courtroom holding areas as an example of strategic redundancy.
“To mitigate risk of catastrophic collapse, the structural system layout encapsulates the typical double court-holding area module on all four sides with seismic moment frames, and by distributing the moment frames around virtually the entire perimeter of the facility,” Youssef says.