Rebar-free, but steel-laden, HPC core shoulders 850-ft. Seattle tower

Sources: Magnusson Klemencic Associates, Lease Crutcher Lewis, and Wright Runstad & Co., Seattle; CP staff

A 58-floor mixed-use tower in Seattle has topped out after a 10-month schedule on the strength of a unique core wall system with requisite volumes of high performance concrete but no conventional rebar. Rainier Square Tower marks the debut of what local engineer Magnusson Klemencic Associates (MKA) dubs the Concrete-Filled Composite Plate Shear Wall (CPSW) system. In contrast to a conventional reinforced concrete wall with large diameter rebar, the system as engineered for the 850-ft. structure redirects steel to composite panels: Half- or ¾-in. thick plates, connected with 1-in. diameter steel cross ties running vertically and horizontally on 12-in. center grids. 

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Seattle Teamsters bask in contract settling disruptive CalPortland strike

Sources: Teamsters Local 174, Tukwila, Wash.; CP staff

Teamsters Local 174 rank & file have approved a four-year contract with the Seattle market’s principal ready mixed operators: CalPortland, Cadman and Lehigh Cement, Stoneway Concrete, and Salmon Bay Sand & Gravel. Ratification of a deal covering nearly 300 drivers had major implications for concrete deliveries in downtown Seattle and areas immediately north, where technology companies and their employees are fueling a wave of mid- and high-rise building projects.

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