Concrete Cast In New Light
by Broderick Perkins
Mix some glass fibers into the crushed stone, cement and water and new light is shed on a centuries old building product. Hungarian architect Aron Losonczi several years ago came up with translucent concrete which gives mere mortals super vision -- sort of. You can't actually see through the new variety of concrete, but is does allow light to pass through -- even while maintaining the same strength and durability of the old fashioned opaque variety. That means, with proper lighting, you can see shadows and outlines of images through the material. Largely experimental and currently too costly to mass produce, translucent concrete is being readied for market by an Aachen, Germany company called LiTraCon for "light transmitting concrete." The firm says the product should be ready for market by the end of 2004. The new material reveals just how sexy something as mundane as concrete can get in "Liquid Stone: New Architecture in Concrete," a National Building Museum exhibit in Washington, D.C. The exhibit celebrates the versatility of concrete -- after water, "the second most widely consumed substance on Earth," and reveals it as a favored material among architects, engineers and others who seek versatility and strength in a building material. Concrete, says the museum, is the stuff of artists, a paradoxical material that begins in a fluid state and must be molded, textured and shaped before it provides strength in both form and function. Found more and more often in and around the home (especially kitchens and baths as well as out of doors and as a framing material), concrete can be colored, patterned and otherwise rendered to meet a host of building needs. Translucence gives it yet more versatility, especially in architectural design, adding a certain lightness of being. Translucent concrete is strong enough for traditional use and it can be strengthened still more. So far its use has been largely demonstrative. By day, thin sheets of translucent concrete in a sidewalk in Stureplan, Stockholm, appear like any other sidewalk concrete. By night subterranean lights give it an ethereal glow. In Fruängenchurch, Stockholm, a church constructed with translucent concrete walls displays the permanently moving shadows of trees outside in a symbolic presentation of light transcending the boundaries of heavy stone. In the home, the material could be used for myriad purposes -- countertops lighted from below, walls, flooring, stairwells that need natural lighting in a power outage and a host of other areas. Along with a host of visions both real and imagined created with concrete, the exhibit also displays a new self-reinforcing concrete which does not need steel reinforcement for added strength. According to Liquid Stone's sponsor, French firm The Lafarge Group, the synthetic fibers in "Ductal" gives the concrete brand the flexibility and strength of steel and may one day make the metal obsolete in building design. The museum's "Liquid Stone" exhibit runs until Jan. 23 and admission is free. | 
