Performance-based seismic design is on a roll, thanks to recent, first-of-their-kind shake-table tests that proved the viability of a “rocking” braced frame that moves seismic design beyond life safety toward build-for-repair. The steel frame not only survived shaking that was 1.75 times stronger than the Northridge earthquake, it returned to its original plumb position after shaking, thanks to post-tensioned strands. Damage was limited to a replaceable fuse, as planned. Slide Show Photo: NEESR-SG The system, tested in Japan, allows an owner to go beyond the minimum code requirements and commission a structure engineered to be repaired after a quake. Related
The U.S. General Services Administration on Aug. 14 let its largest stimulus-funded project so far, a $435.4-million design-build contract for the new U.S. Coast Guard headquarters building in Washington, D.C. Clark Construction Group of Bethesda, Md., led the winning team, joined by St. Louis-based HOK, which will provide interior designs, landscape architecture, construction documents and administration. The Washington office of WDG Architecture is architect-of-record. Chicago-based Perkins+Will created preliminary designs and bridging documents for the 1.2 million-sq-ft building, which will aim for a LEED Silver rating. The headquarters, along with a 1,000-car parking garage, will be built on the new 4.5
A 40-second test in Japan on the world’s largest shake table demonstrated for the first time that wood-framed mid-rise buildings can be built to withstand major earthquakes, say researchers. The simulation of a magnitude-7.5 quake on a six-story residential building caps a $1.4-million research project that is elevating performance-based seismic design of wood frames. The work is expected to result in new standards for mid-rise wood buildings, which rarely are allowed in quake zones. Photo: Neeswood and Simpson Strong-Tie World’s largest shake table helped demonstrate the viability of performance-based seismic design for wood frames. During the July 14 test, the
A magnitude-7.5 quake, simulated by a shake table on July 14, proved performance-based seismic design is valid for a six-story, wood-frame residential building on a one-story steel frame. Damage was negligible, say investigators from Colorado State University and Simpson Strong-Tie. Photo: Simpson Strong-Tie Company Inc. Related Links: Jumbo Quake Test Validates Design: Magnitude 7.5 Tembler Jolts Connections
Zaha Hadid Architects, London, has unveiled its plan for a 525,000-sq-meter office and retail development in New Cairo, Egypt, a satellite district east of Cairo. The Stone Towers development will include 18 office buildings containing 28,000 employees and 1,400 luxury apartments within a 45-acre site surrounding sunken gardens. The project owner is the Rooya Group. New Cairo is already home to 350,000 residents and is targeted as a hub for multinationals living in Egypt. New Cairo’s population is projected to reach 2 million by 2020. Photo: Zaha Hadid Architects
Architect Ellerbe Becket, Kansas City, has been retained by Nets owner and Atlantic Yards developer Bruce Ratner, of Forest City Ratner Cos., to come up with a new design for the long-delayed and controversial Atlantic Yards basketball and entertainment arena in Brooklyn, N.Y. Ellerbe Becket replaces Gehry Partners. Other key designers, New York City-based structural engineer Thornton-Tomasetti, and mechanical-electrical-plumbing engineer, WSP Flack + Kurtz, will remain on the project. Forest City Ratner says it hopes to unveil new images of the arena, named Barclays Center, in late June and that it intends to break ground later this year in anticipation
Crews recently topped out the $640-million Walter Reed National Military Medical Center in Bethesda, Md. The design-build project is being constructed on the site of the existing National Naval Medical Center as part of the Base Realignment and Closure Act of 2005 by a joint venture of Clark Construction Group, Bethesda, and Balfour Beatty Construction, Fairfax, Va. When completed, the building will feature a new 560,000-sq-ft ambulatory care clinic and a 165,000-sq-ft in-patient addition to the existing hospital. The team also is constructing an eight-story, 944-space patient parking garage, a 700-ft-long logistics tunnel and 450,000 sq ft of phased renovations
The third draft of the nation’s first standard for high-performance buildings, currently out for public comment through June 15, has stricter energy conservation provisions and reflects input from a broader cross-section of experts, according to its developer. National laboratories currently are using energy modeling to determine how much more savings could be generated using the latest version of the proposed standard compared to previous versions. “I would anticipate [savings would go] up at least another 5%,” says Kent Peterson, chair of the committee writing American Society of Heating, Refrigerating and Air-Conditioning Engineers Standard 189.1, and principal of P2S Engineering Inc.,
Structural engineers from Keast & Hood are a bit baffled in the belfry of historic Independence Hall in Philadelphia. As part of a planned $4.3-million renovation, triggered by leaks in the landmark’s tower, the local firm discovered that several lines of iron rods, which run vertically down the center of the tower’s 2.75-in.-thick wooden siding, have significantly deteriorated. But the team doesn’t know why the rods are there in the first place, so they don’t know if they need to be repaired or replaced. Photo: National Park Service Philadelphia tower built in 1828. Photo: National Park Service Purpose of rods
This summer, Sears Tower will have a new face to match its new name. Although Chicagoans are less than thrilled about Willis Group Holdings moving in, the new view atop “Willis Tower” may render them speechless. Image: SOM Sears Tower’s observation floor will extend visitors beyond the curtain wall. Image: SOM Innovative glass boxes will provide gut-wrenching views from Chicago’s tallest tower. Just outside the glassed-enclosed, 103rd-floor skydeck, construction is under way to offer visitors a view of the city at all angles, including straight down, by means of four laminated, structural-glass modules that will extend more than 4 ft