27 October 1997
Source: Engineering News Record (ENR), October 20, 1997, pp. 8, 10
Some 30 months after the bombing of the Alfred P. Murrah Federal Building in Oklahoma City, the General Services Administration continues to refine and implement its guidelines for designing and building secure and blast-resistant facilities. But the work is done under a veil of secrecy, and implementation is not exactly the same for any two sites.
To avoid a breach of security, GSA says it has no plans to make public the still-evolving guidelines. Even designers and contractors with a federal track record won't see the specifics for a site until they are picked for a particular project, says GSA.
The cost of higher security is in the public domain. Since the June 1995 release of a U.S.Justice Dept. building-vulnerability assessment, prompted by the April 19, 1995 Murrah bombing, GSA has spent $101.3 million on operating expenses. They include such items as additional guards, plus $118.8 million on capital equipment, such as new magnetometers, X-ray machines and other equipment. The measures have doubled GSA's annual operating costs for its nearly 8,000 owned and leased buildings.
During interviews with firms competing for a GSA design contract, the agency discusses security features, but only in general terms. The winning firm receives the detailed requirements. Contractors then see security features as part of a project's drawings and specifications. But all firms must sign an agreement that they won't disclose the requirements.
GSA guidelines, which vary from project to project and site to site, are not likely ever to be cast in stone. "It's a work in progress," says Edward Feiner, GSA's chief architect.
Soon after the Murrah disaster, the agency began making changes in federal projects. For example, in mid-1995, construction had just started on a 306,000-sq-ft Federal Bureau of Investigation field office in Washington, D.C. At the FBl's request, GSA directed a redesign to add unspecified improvements in the facade, structure and other components. The new blast protection cost $5.9 million for construction and $1 million for design, out of total project cost of $93.4 million, according to GSA. [Photo omitted]
At other projects, including a 200,000-sq-ft federal courthouse in Brownsville, Texas, and a 254,000-sq-ft courthouse-office building in Albuquerque, setbacks from the road were increased, says Connie Oliver, a spokeswoman for Centex Construction Co., Dallas, the contractor for both buildings. The amount of bulletproof glass was increased for the Albuquerque building, particularly on lower levels of the seven-story facility, she adds.
Says Paul Ashlin, a vice president with Lehrer McGovern Bovis Inc., New York City: "What I have seen has been more emphasis on the sitework," such as landscaping to prevent vehicular access.
Back in its offices, GSA continues to refine its standards. The latest version of the guidelines was issued in January to GSA regional offices. Though GSA officials will not release a copy of the document or discuss its details, they do say the guidelines cover all aspects of a building, including landscaping, setbacks and the exterior. And there is guidance on ways to avoid the kind of progressive collapse that occurred at Murrah.
The agency developed the benchmarks through extensive consultation with outside security and engineering specialists but officials emphasize that security requirements vary with each project.
"There will be no cookie-cutter approach," says Wade Belcher, security standards director with GSA's Public Buildings Service. Belcher adds that GSA's guidelines aren't manuals on structural, mechanical or electrical systems. Rather, adds Feiner, "It's a performance-based approach" that attempts to be smarter in the assembly of various components within the design. But GSA doesn't want fortress designs. "These are not [military] installations, says Feiner. "These are public buildings in the hearts of major American cities."
By Tom Ichniowski with Rob McManamy
SUSTAINABLE DEVELOPMENT FOR THE next millennium was supposed to be the theme at this month's annual meeting of the American Society of Civil Engineers in Minneapolis, but lessons from the past forced many of the 2,400 attendees to brush up on their history before embracing the future.
Presentations on the Oklahoma City bombing, Northridge Earthquake and L'Ambiance Plaza collapse during the week of Oct. 5 drew solid crowds and animated discussion, further proof that all three events still are affecting current policy and building methods. Panelists at the Oklahoma City session noted that the U.S. General Services Administration has developed new defensive design requirements for federal buildings (see above). The ASCE panel suggested that some different approaches in design could have prevented cataclysmic structural damage to the the nine-story Alfred P. Murrah Federal Building in April 1995 despite the immense size of the bomb.
Just a small amount of additional reinforcing steel in lateral bracing likely would have prevented much of Murrah's progressive collapse, claimed panelists Gene Corley, a vice president with Construction Technology Laboratories Inc., Skokie, Ill., and NewYork City-based structural engineer Charles Thornton. Thornton also noted that the building had virtually no stand-off distance from the street, an outdated feature that defensive design precepts would not permit now. "Had [Murrah] been designed today, there would maybe be 80% less damage," he said.
Damage to thousands of buildings around Los Angeles in the January 1994 Northridge Earthquake still has much of the engineering community wondering. "Ironically, the lowest quality of [steel welding] workmanship resulted in the lowest cost of repair," notes Duane Miller, a welding design engineer with Lincoln Electric Co., Cleveland, Ohio. "[Poor] connections just separated, but the better ones saw damage [transferred] to the flanges."
A decade ago, blame for the 28 deaths at the L'Ambiance Plaza collapse in Bridgeport, Conn., was fixed on the liftslab building technique. This month, one of the investigators of that accident is trying to resurrect lift-slab. " [It] can be a safe and efficient way to construct a building as long as certain guidelines are followed," says David Perazza, a structural engineer with LZA Technology, New York City. "Many precautions weren't taken at L'Ambiance . . . and the technique has suffered for it." ASCE will issue new guidelines for lift-slab work within a year.