Guidelines for the performance-based design of structures to resist disproportionate collapse are under development by the American Society of Civil Engineers' Structural Engineering Institute. SEI expects to release a draft next year and publish the guidelines in 2013. “We are providing guidelines for those who wish to use them. We are not mandating use,” says Robert Smilowitz, chairman of the SEI's disproportionate collapse standards and guidance committee and a principal at structural engineer Weidlinger Associates Inc., New York City. “Our immediate objective is to provide a solid technical basis for designing structures that are more resistant to disproportionate collapse. It
The State Dept. is pushing ahead with plans to embrace “design excellence” in its embassy construction program, using some elements for a new U.S. embassy in London, now in design, and fleshing out details through a series of documents that will spell out specific Design Excellence program guidelines. Photo: U.S. Department of State / Bureau of Overseas Buildings Operations / Timothy Hursley The Bureau of Overseas Buildings Operations used some Design Excellence elements as it planned and built an embassy in Beijing that was completed in 2008. Image: U.S. Dept. of State/Bureau of Overseas Buildings Operations For the new U.S.
Work on the nation's first public repository for data on disaster and failure events is under way. The National Institute of Standards and Technology expects to launch a pilot website for a broad disaster database early next year. Events stemming from earthquakes, hurricanes, tornadoes, windstorms, community-scale fires, structural fires, storm surges, floods and tsunamis are included in the repository. Photo: Courtesy Nelson Architectural Enegineers Inc. Investigating engineer had to wait five years to sound alarm about flawed truss-joist product. “The effort will support development of standards and technologies for effective collection of data on disasters and failures,” in addition to
Research is getting under way to develop prescriptive code language and performance-based design guidelines for a “rocking frame” structural system that relies on vertically post-tensioned shear walls for seismic resistance. The system promises to improve seismic performance, reduce rebar congestion and enhance constructibility, says the engineer developing it. Photo: Courtesy of Tipping Mar Placing vertical post-tensioning tendons in ducts in concrete shear walls is known to reduce rebar congestion and simplify construction. Drawing: Courtesy of Tipping Mar “We believe these advantages could significantly impact seismic design and construction of mid-rise and high-rise concrete buildings,” says Steven Tipping, president of structural
Southern Nevada’s Nellis Air Force Base is trimming construction costs of a new child development center by nearly 4% by using a unique aerated plastic-riser foundation system. Graphic: Courtesy USAF Cobblestone Construction, Las Vegas, broke ground on the $7.2-million design-build project in August 2010 and later discovered that the six-acre site along the northwest edge of the base was contaminated with radon. The 26,000-sq-ft block building consequently required a gas ventilation system, which typically comprises a vapor barrier consisting of a membrane of washed rocks and liquid as well as perforated pipe and fans. Wright Engineers, Las Vegas, proposed a
The Pacific Earthquake Engineering Research Center is calling on seismic engineers, government agencies and researchers to try out a “live” beta version of a web-based interactive tool that will allow them—free of charge—to search, extract and download recorded ground motions for the analysis and design of earthquake-resistant structures. Seismic engineers familiar with the tool are already lauding it, especially for use in performance-based earthquake engineering. Photo: Courtesy of Peer Web-based app lets engineers explore many seismic scenarios. The 2010 PEER Ground Motion Database allows users to select ground-motion records to match the seismic code’s response spectrum or a customized site-specific
A Nottingham, N.H., public works employee was gassing up his truck when he heard a noise and suddenly the roof of the town’s highway maintenance garage collapsed.
Code crafters are lauding a significant process change in reference-standard development that provides markers for progress along the way, directional signals for reaching goals and validation of the standard’s potential impact on energy use and cost. The process, based on energy modeling and analysis, helped the developers of the 2010 edition of the commercial-building energy standard reach their goal of providing a standard that, if followed, could result in a whopping 30% reduction in both energy use and costs compared with use of the standard’s 2004 edition. Crafters of the next edition of the energy standard already are using the
Hoping for a bigger Super Bowl attendance at the Cowboys Stadium in Arlington, Texas, the owner arranged for temporary sections to increase seating capacity. But some of those seats were not ready at game time. Eric Grubman, NFL executive vice president, said the problem was officials “just ran out of time” to complete infrastructure such as railings and steps, and to tighten risers. The stadium owner says that the $1.3-billion stadium was designed to fully accommodate the additional seats. Seating Solutions, the Commack, N.Y.-based contractor charged with installing the temporary seats, had no comment.
Keith Howells, newly installed chairman of London-based global design firm Mott MacDonald Group, is optimistic that Dubai’s gradual emergence from its real estate slump will boost the firm’s fortunes this year. Mott’s recent award of a design contract on the $6-billion Dubai Pearl mixed-use project supports his view that the emirate’s construction market is climbing “off the floor.” Photo: Courtesy of Mott MacDonald Group Keith Howells takes over as chairman of Mott MacDonald Group just as the firm wins a design award on a $6-billion Dubai development. Mott’s work involves design of mechanical, electrical, public health, fire, communications and security