Associate Geotechnical Engineer Hamilton Puangnak was featured in a recent video from DCI Engineers showcasing the unique challenges and innovative design of The Artise, a 25-story office building completed last year in downtown Bellevue, Washington.
The Artise is part of a wave of new high-rise developments in the city’s core, and GeoEngineers is proud to have contributed to this growth. To date, Hamilton has provided performance-based seismic design services for nearly 50 high-rise projects, including The Artise. For this project, Hamilton and our team applied this approach to deliver advanced earthquake engineering solutions and validate several innovative designs.
GeoEngineers provided geotechnical design services for The Artise as part of a design-build team led by Schnitzer West, Sellen, NBBJ, and DCI. The 25-story, 600,000-square-foot office tower at 106th Avenue and Northeast 8th Street that faced a variety of challenges due to site constraints, last-minute changes to the design criteria, and an accelerated timeline. The video from DCI highlights the building’s structural innovations, including an unusual Buckling Restrained Brace (BRB) system involving super braces that skip floors and fluid viscous seismic dampers—a first in the city.
In recent years, GeoEngineers has cemented its reputation as a go-to firm for seismic engineering and geotechnical services for complex urban high-rises in the Seattle and Bellevue markets. Projects like The Artise come with a unique set of geotechnical and site challenges that often require a more specialized and site-specific approach.
Engineers use performance-based seismic design when standard, code-based design criteria may not be appropriate. Typically, designers use prescriptive seismic design criteria from reference standards, such as ASCE 7, or the International Building Code (IBC). These prescriptive procedures can be inefficient and overlook complex site-specific features. For example, tall buildings within the Seattle basin face increased seismic hazard compared to similar buildings outside sedimentary basins.
“The soft soil and rock in the basin amplify long-period waves,” says Hamilton. “Tall buildings resonate at a similar frequency, making the seismic forces acting on the structure that much stronger.”
The City of Bellevue requires performance-based seismic design approach for most buildings over 240 feet tall. This process allows engineers to fine-tune seismic parameters based on a site’s unique conditions—allowing for greater flexibility and responsiveness in design.
Performance-based seismic design can also involve numerical modeling to design and validate excavation support systems, which is critical for deep urban excavations. Urban high-rise sites are often lot-line to lot-line, so neighboring buildings and infrastructure are immediately adjacent to deep shored excavations. That means strict deformation control for the temporary excavation support systems that protect the adjacent buildings and infrastructure. GeoEngineers’ Artise team used numerical modeling to find an efficient but non-standard soil-nail support system that did exactly that.
Projects like The Artise are continually pushing the boundaries of geotechnical and seismic design. Our team’s experience in performance-based design and advanced numerical modeling is helping to shape the skylines of Seattle and Bellevue while ensuring that high-rise developments like The Artise are both safe and efficient.
