High-Profile Panels

Architectural precast for Los Angeles’ new 42-story, 147-unit luxury condominium tower, The Century arguably the tallest concrete building west of the

Architectural precast for Los Angeles’ new 42-story, 147-unit luxury condominium tower, The Century Û arguably the tallest concrete building west of the Mississippi Û was equal to the demands of both seismic zone construction and Beverly Hills’ beauty quotient. Clark Pacific’s nearby Fontana headquarters facility supplied 1,147 panels for the project. Of that total, only 42 units are flat; among the majority, varying radii, sometimes within a single panel, conform to the tower’s curves. Highlighting the fa¡ade are Italian travertine-faced precast panels cladding balconies at the fourth through 10th floors.

Clark Pacific Engineering Manager and Project Executive Renaldo Lozano attributes the job’s smooth implementation largely to intensive preconstruction planning by design-build team members, who met weekly for several months to weigh alternatives and refine details. HKS, Inc., served as the project’s architectural firm of record, while Webcor Concrete of San Mateo, Calif., acted as concrete contractor. Noting a precedent of Clark Pacific and Webcor collaboration, Lozano affirms, We have a strong record of working together to bring projects in on an accelerated schedule. San Francisco’s St. Regis Museum Tower Û a 42-story reinforced concrete structure rivaling The Century in height Û is one such building on which both companies joined forces in 2004.

Not least among challenges of The Century project was erection sequencing on a tight job site. The tower’s base incorporated hand-set stone for the first three floors and precast cladding for east and west podium exteriors. Above the base, precast erection followed the cast-in-place cycle of one floor every six days at a remove of seven or eight floors. Trailing placement of Catalina Pacific-supplied ready mixed since January, precast installation thus progressed at the rate of one level enclosed every six days. Panel-erection time per floor, Clark Pacific reports, ranged from eight to 10 hours.

Two tower cranes were required to accommodate the full perimeter of each floor during C-I-P and precast construction. Freeing up blocks of time for the tower crane was a crucial part of scheduling, reports Clark Pacific Senior Project Manager Sam Argentine. Flying forms and rebar at every level had to be coordinated with precast erection, since space was too limited for simultaneous operations.

The limited footprint also required strategic maneuvering of vehicles on the job site in the midst of erection. Five to six truckloads were needed to deliver 22-26 panels per floor. For some levels, as many as 12 to 13 panel loads were delivered. Nonetheless, Clark Pacific anticipates early 2009 completion for the bulk of precast work. A wrap-up in March, entailing alignment and welding, will follow a brief period of downtime for man-lift removal.

VERTICAL FOOT RACE REACHES APEX IN GOLDEN STATE

At 42 stories, the St. Regis Museum Tower in San Francisco may be said to rival The Century as tallest concrete building west of the Mississippi. Providing a height advantage for the Los Angeles structure, however, are The Century’s typical 10-ft. 8-in. floor-to-ceiling heights, plus 12-ft. 4-in. heights about every eight floors.

Clark Pacific supplied precast for the St. Regis Museum Tower from its West Sacramento facility. The cast-in-place and architectural precast tower houses a five-star hotel, with 269 high-end hotel rooms; 102 luxury condominiums; and, the three-story Museum of African Diaspora. The 750,000-sq.-ft. project also includes a four-level subterranean garage.