|
 |
 |
 |
 |
 |
 |
 |
 |
|
|
Indeed, it was an earthquake that signaled the beginning of the end for the existing Bay Bridge – built in 1936 at a cost of $77 million. It accommodates more traffic than any other bridge in the US, but an earthquake in 1989 damaged the structure and highlighted how it was designed for only minimal seismic levels. A decision was therefore taken to replace the old 3.50 km (2.18 mile) bridge with a new $2.5 billion bridge. Contractor KFM (a joint venture between Kiewit Pacific, FCI Constructors and Manson Construction Co.) selected Potain MD 560-40 tower cranes because the product’s 40 t (44 USt) heavy lift capacity and proven workhorse capabilities when setting structural steelwork, lifting in precast concrete panels and the like made it a natural for the job. The Potain MDs are being used to build the ‘Skyway’ viaduct, a 2.5 km (1.5 mile) long segment of the bridge. Each crane stands on 28 piers, 50 m (164 ft) high in 15 m (50 ft) of water. The Potains towers sit on bespoke pile-supported concrete pads adjacent to the piers and are helping with form and rebar placement, along with a range of general lifting duties. These 560 tonne-meter machines – erected and serviced by SI Equipment – have jib lengths of up to 80 m (262 ft) and a tip capacity at maximum radius of 3.4 t (4 USt). The 14 units at work at the Bay Bridge have all been set up with differing configurations, depending on the specific requirements at each pier. One of the MD 560-40 tower cranes is based at KFM’s precast concrete yard, where roadway sections are being made. A total of 452 sections are needed for the Skyway viaduct, each up to 9m (30 ft) high, 27 m (90 ft) wide and 8 m (25 ft) long – and weighing up to 708 t (780 USt). These sections are then floated into the Bay by barges and connected, like huge building blocks, to form the bridge deck. These sections are designed to sway and slide during an earthquake. This is accomplished through a hinge beam system of expansion joints that use steel tubes placed in the deck segments. Acting like shock absorbers, the tubes will allow the segments to slide during the expansion and contraction of a quake, preventing damage to the structure. The intention is for the bridge to remain operable after a quake, thereby allowing emergency services access to the City. This section of the new bridge is being constructed at a cost of $1.04 billion. It represents the most expensive construction contract awarded by the state of California. Work is expected to be complete around 2007. About The Manitowoc Company The Manitowoc Company, Inc. is one of the world's largest providers of lifting equipment for the global construction industry, including lattice-boom cranes, tower cranes, mobile telescopic cranes, and boom trucks. As a leading manufacturer of ice-cube machines, ice/beverage dispensers, and commercial refrigeration equipment, the company offers the broadest line of cold-focused equipment for the foodservice industry. In addition, the company is a leading provider of shipbuilding, ship repair, and conversion services for government, military, and commercial customers throughout the US maritime industry. ##### For More Information Contact: Tom Cioni Manitowoc Crane Group Tel: + 1 920 683 6510 E-mail: tcioni@manitowoccranes.com Ben Shaw SE10 Creative Tel: +44 1829 549609 E-mail: shaw@se10.com
About The Manitowoc Company
# # #
|
| |||||||||||||||||||||||||||||||||
| ©2008 The Manitowoc Company, Inc. | ||
|
For Immediate Release
