Structure Type: Canopy
Project Scope: Design, engineering, fabrication & installation
Project Size: 38,595 SF
Material: PTFE & AESS Steel
Location: Redmond, WA
Completion Date: April 2024
Market Segment: Infrastructure
Owner: City of Redmond
Canopy Designer/Engineer: FTL Design Engineering Studio (now part of TYLin)
Bridge Designer: AECOM
General Contractor: Kiewit
The undulating Redmond Technology Station Pedestrian Bridge canopy provides a safe, shaded traverse for pedestrians and bicycles over State Route 520 in the Overlake neighborhood. The 1,100’ long by 50’ wide bridge crosses more than 20 lanes of roadway and two sets of light rail beneath. At roughly a quarter of a mile long, the series of large interconnecting white PTFE canopies provide a wide walking path, two lanes for bicycles, benches, and landscape planters unifying Microsoft’s 500-acre campus.
Enclos Tensile Structures (ETS) provided design-assist services to the engineer for the PTFE Membrane structure, which included 110 tons of architecturally exposed structural steel (AESS). The steel structure includes bolt-spliced rolled pipe sections beneath the PTFE and stainless steel catenary cables clamping the membrane’s edge between the rolled sections. Nearing the center of the bridge, the apex of the membrane and steel masts increases in height, creating daylight oculi that are penetrated by the supporting column. Special integration of a lighting ring detail was coordinated with the design team to create a safe environment beneath the canopy at night by illuminating the underside of the PTFE membrane. Additionally, the design geometry required each bay to be unique, which in turn required each structural steel component, each membrane cable assembly length, and each of the 33 PTFE membrane assemblies to be unique.
The steel and membrane scope of work on the Redmond Technology Center (aka “RTS”) Pedestrian Bridge is an excellent example of ETS’ preferred scope of Base Plates Up.
Photo credit: Geekwire