The American Society of Civil Engineers (ASCE) has announced five finalists for the group's annual Outstanding Civil Engineering Achievement (OCEA) award. Previous OCEA winners have included the World Trade Center, the Trans-Alaska Pipeline and other high-profile megaprojects, as well as a range of lesser-known bridges, roadways and restored or relocated buildings. The 2010 OCEA winner will be announced at an award ceremony in the Washington, D.C., area on March 25th, but out of 28 entries, here are the five that scored the highest with the jury (of which, for full disclosure, I was a member). Although these represent the jury's overall favorite projects, based on innovation in construction and materials, public benefit, impact on the physical environment, and other judging criteria, they are listed here in alphabetical order, not by score or personal preference.
Central Link Section 710 Seattle, Wash.
Whether you are a believer in the universal services are public transport, this project deserves to be respected. To build a passenger station in the Beacon Hill area, south of downtown Seattle, was the party's largest and deepest soft soil sequential excavation method (SEM) to create tunnel in North America. SEM refers to the practice of digging a tunnel in sections, go to support each segment as you. The couple mile long tunnel part of a 14-mile light-rail project were almost twice as depth and diameter of the previous such projects, which under a 352-meter-high hill. As a first test shaft, a surprisingly large amount of fine sand found, engineers quickly design and location of the tunnel, ground-breaking new construction techniques that future projects should benefit SEM in soft soils reorganized. The end result is, by nature, modest-the Beacon Hill station 160 feet underground, on the Internet in 20 seconds with the lift-so of the 642-ton, 330-meter-long earth pressure balancing tunnel boring machine, that the tunnel must be dug as proof of this nimble and literally ground-breaking project.
Concordia University Wisconsin Lakeshore Environmental Enhancement and Education Project
Mequon, Wis.
This is one of the smallest of the projects submitted to the jury, but also one of the most intelligent. Concordia University Wisconsin (CUW) asked engineers to go to an eroding coastline-some 20,000 tons of sediment annually lost, but also to meet increasing public access promenade. The $ 7,600,000 project stabilizes a 130-meter-high, 2,300-meter-long bluff along the eastern shore of Lake Michigan, with protective properties that appear completely natural. Boulders placed strategically in the water serve as armor stones, breaking the power of incoming waves, while a perched wetland absorbs rain water. Without going into before and after photos, it would be easy to assume that the area was always naturally enhanced and not the work of extensive 3D CAD and hydraulic computer models, water-tank testing and careful placement of 100,000 tons of rock, stone and plants.
Metropolitan Water District of Southern California Arrowhead Tunnels
Hemet, Calif.
Water is a big deal in Southern California, is where the demand for it continues to climb, and experts fear a major earthquake a dangerous shortage of drinking water could be thrown. The 2009 OCEA Winner Orange County ground water replenishing system helped address the first part of this equation, increasing the supply of clean water. The arrowhead tunnels are designed to increase supply and to prepare for the worst. The combined 9.6 miles of tunnels to provide six months of emergency water for about 15 million inhabitants. The impetus for this section of the 44-mile-long Inland Feeder Project was its greatest challenge-the tunnel running east of the San Andreas Fault, and by 20 fault lines. Similar to the Seattle project, a new drilling techniques, including use of the probe holes soil conditions before the giant tunnel boring machines (TBM) judge necessary. With the new probe system, and the use of DMS actively monitor the TBM tunnel pressure were able to dig faster, with fewer stops and starts. The real test of the tunnel is its ability to oppose an earthquake and the support of the local population in the aftermath. But now this seems complex and difficult project to $ 500 million U.S. dollars well spent.
Sutong Bridge
Jiangsu Province, China
Like it or not, the current home of the state-of-the-art civil engineering megaproject is China, where the Shanghai Financial Center has recently become the second-tallest building on the planet. Even more visible, though, is the Sutong Bridge, which at 1088 meters (3570 feet) is the world's longest cable-stayed bridge, and the first whose main span exceeds 1000 meters. Engineering "firsts," though expensive and the cause of national pride, can be short on purpose, aesthetics or real innovation. The Sutong is another story: This stunning bridge replaces a cumbersome and potentially dangerous 4-hour ferry ride between Nantong and Shanghai with a 1-hour drive, and the project utilizes a new kind of zinc-galvanized-steel strand that reduces the diameter of its cables, cutting wind drag. Building a bridge in the Yangtze River meant breaking another record—at 120 meters, the Sutong has the deepest foundation of any cable-stayed bridge. As for whether the concrete and steel bridge towers needed to be 300 meters—breaking yet another record—sometimes the most responsible engineers can get a little carried away.
Utah State Capitol Seismic Base Isolation and Restoration
Salt Lake City, Utah
When the Utah State Capitol building, located several hundred feet from an active fault capable of a magnitude 7.3 earthquake, failed seismic evaluations, state authorities had two choices. Either replace the entire building, at a cost of up to $1 billion, or figure out a way to reinforce and base-isolate—making the building essentially float on its foundations—an architectural masterpiece that's more than a century old. The latter meant tackling one of the biggest and most delicate base-isolation projects to date. Because of the nature of the structure and the age of its concrete, the foundations would have to be pulled out without raising or lowering the 132-million-pound-building by more than 1/16th of an inch. Ultimately, contractors surgically installed 265 base isolators, while reinforcing the iconic dome and other structural elements. The project cost a comparatively modest $212 million, and turned what was a disaster waiting to happen into one of the most earthquake-resistant buildings in the country.
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