Precast in Many Forms
Precast concrete is an architectural material with a unique combination of strength and versatility. In the hands of an imaginative designer and an expert fabricator, it can assume a rich variety of forms, textures, and colors, while performing an array of structural and decorative roles. In selecting four projects for its 2003 awards program, the Architectural Precast Association sought to demonstrate the imaginative application of these properties and to highlight the benefits of collaboration between architect and fabricator.
Typically produced in a plant away from the construction site, precast concrete can be formed into virtually any shape to create structural elements or flat panels articulated with copings, returns, soffits, jambs, or sills. Cast-in hardware can be positioned for structural reinforcement or to facilitate installation. Geometric designs and lettering can be "molded" by the forms. Materials such as natural stone can be placed in the form before the pour to become the resulting surface finish, or panels can be cast with cavities for later installation of tile or brick.
The appearance of precast concrete can be further modified through selection of its components: cement, pigments (usually iron oxides), sand, and coarse aggregate (crushed rock, pebbles). Surface textures can also be modified by the material of the forms and the treatment of the unit after curing. The coarse aggregate can exposed by sandblasting, while light sandblasting produces a sand texture, and acid etching makes a surface resembling natural stone.
All these fabrication variables create design opportunities. According to Peter Stroyan, managing director of Bespoke Concrete Products Ltd., there's been a recent change in the use of this material. He states: "For many years the typical precast units were rectangular in shape with a flat grey finish... but the relative ease with which an almost unlimited range of shapes, designs, colors, and textures can be produced has stimulated the imagination of engineers and architects."
APA Award Winners
One of those so inspired is the firm of Thompson, Ventulett, Stainback and Associates working with Castone Corporation to build the Glenridge Highlands office complex in Atlanta. The precast panels for this mixed use development exhibit sophisticated effects such as washed aggregate finishes of Tifton pink rock blended with red pigment. Lighter panels were cast with Lagrange pink rock and black and red pigment, then given a light sandblast texture. The designers applied precast methods to make columns, spandrels, punched window openings, beams, and a cantilevered "eyebrow."
Receiving a commendation in the awards program is the Walt Disney's California Adventure Amusement Park Building in Anaheim, California designed by Walt Disney Imagineering working with Architectural Cast Stone of Santa Ana, California. The project uses cast stone blocks made in the style of the "Textile Blocks" of Frank Lloyd Wright. To replicate Wright's design themes, they used white cement with colorants and the "Vibrant Dry Tamp" method. With this method, fabricators use handheld pneumatic rammers to consolidate the mix into the rigid molds, simulating the appearance of sandstone, with sharp edges.
Harwood K. Smith Architects worked with International Concrete Products, Inc. of Germantown, Wisconsin to build Miller Park in Milwaukee, a major-league baseball facility. The facade is constructed of 475 precast simulated limestone panels with inset brick. The awards jury commented that this facade relates successfully to the pedestrian scale and "...serves to reconnect the traditions of Milwaukee as a city and the American tradition of baseball."
The Two Freedom Square Office Building was designed by SmithGroup and precast manufacturer Arban & Carosi, Inc.. Large precast corner panels nearly 30 feet (9 meters) in height were crafted with many precisely aligned horizontal joints. The jury noted: "The clean-cut, extremely well coordinated castings bear witness to the architectural opportunities available in the precast industry... The recesses, edges, corners, sills, headers, spandrels, wall panels and all of the precast units are integrated with great care."
The jury for the Architectural Precast Association's Awards for Design & Manufacturing Excellence Competition included Carlton Sturges Abbott, FAIA, of Carlton Abbott and Partners; Philip Esocoff, FAIA, of Esocoff & Associates Architects; Byron Rucker Dickson, of Dickson Architects & Associates/PC, and
Kevin Bertholf, of Architectural Concrete Products, Inc.
Award-winning Glenridge Highlands office complex, demonstrating exemplary use of precast concrete, by Thompson, Ventulett, Stainback and Associates and Castone Corporation.
Photo: Castone Corporation
Walt Disney's California Adventure Amusement Park Building, reminiscent of the work of Frank Lloyd Wright, designed by Walt Disney Imagineering and Architectural Cast Stone.
Photo: Architectural Cast Stone
Miller Park, a major-league baseball facility, by Harwood K. Smith Architects and International Concrete Products, Inc.
Photo: International Concrete Products, Inc.
The Two Freedom Square Office Building by SmithGroup and Arban & Carosi, Inc.
Photo: Arban & Carosi, Inc.
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