Reducing steel requirements by 10 percent while designing the new downtown Los Angeles courthouse’s structural system

About the customer

Skidmore, Owings & Merrill (SOM) is a renowned global architectural, urban planning and engineering firm. Known for some of the world’s most technically and environmentally advanced buildings, SOM applies creativity and emerging technologies to design buildings for the future. The firm has won more design awards than most other architectural practices and is known for buildings such as the Burj Khalifa (Dubai), Willis Tower (Chicago) and many more. With its eyes set on a sustainable future, SOM leads the way in building the impossible.

Their challenge

SOM designed the new United States Courthouse in downtown Los Angeles to be an open and transparent public space. To comply with regulations from the General Services Administration’s (GSA) 2020 objective, the building includes many sustainable design features. SOM’s structural engineering team delivered a timely creative structural system to suspend the perimeter of the building above the civic plaza, incorporating the appropriate setbacks from the street.

Our solution

Designers and engineers at SOM are constantly considerate of the materials used in projects and aim to create designs that use less materials to reduce costs and the environmental footprint. With this in mind, a perfect addition to enhance their design workflow was Simcenter™ Optistruct® software, which is part of the Siemens Xcelerator business platform of software, hardware and services. Starting from a blank slate, SOM improved the roof’s structural design, exploiting advanced optimization techniques in a two-phase approach. SOM’s team utilized Simcenter Optistruct topology optimization to create design options by applying loads and constraints with the goal of generating an initial organic-like optimal load path. Then as a second stage beam optimization phase to individuate the best type of steel sections. A great synergy between Simcenter Optistruct technology and SOM’s expertise allowed the team to create the best iteration for the final design.

Structural system and framing layout. Photo courtesy of SOM. TOP: Optimization iterations and final optimized truss. Photo courtesy of SOM.

Results

The structural design specialists at SOM used Simcenter Optistruct to generate an ideal project plan that considered sustainable regulations and manufacturing constraints. With this unique design, SOM was able to minimize the weight of the building and use fewer materials, resulting in reduced costs for both the client and contractor. Specifically, the SOM team reduced the steel needed by 10 percent while improving the global performance of the structural system. The building received Leadership in Energy and Environmental Design (LEED) Platinum certification and reached the GSA’s 2020 energy objective. It has also won more than 35 awards for its creative and timeless architectural and structural design.

“Using Simcenter Optistruct provided many design options for our team, and we were able to use the analysis results to inform our final design,” says Alessandro Beghini, associate director at SOM. “This project had many architectural requirements and structural challenges, but by working with Siemens and other optimization software we were able to succeed efficiently.”

Construction phase. Photo courtesy of SOM.