Traveling along the Trans-Canada Highway in southeastern British Columbia will be a little easier, safer, and quicker this December when a stretch of highway will be upgraded from its current two-lane configuration to a four-lane highway. Flatiron Constructors Candad Canada Ltd. of Richmond, B.C., is the primary contractor for the CAD$40 million project. It also offers access and intersection upgrades for the Revelstoke to Golden segment of the Trans-Canada Highway.
Two new bridges are being built to help expand the highway’s capacity, one over the Canadian Pacific Railroad and a second crossing the Columbia River at Donald. At approximately 1,000 ft. long, the Donald Bridge posed some interesting on-site logistical challenges for Flatiron’s workers. “With steep slopes, a small workspace, and not a lot of room to move around, access was very limited for bridge construction,” said Rick Morrison, project manager for Flatiron Constructors Candad Canada. “We also had to move our main crane across the river several times.”
To support construction efforts of the Donald Bridge, Flatiron brought in three Terex crane models: a Terex RT 780 rough-terrain crane; a Terex HC 110 hydraulic crawler crane; and a 230-ton Terex HC 230 crawler crane. The smaller RT 780 and HC 110 cranes were used for support projects, such as assisting with bridge substructure building, pier work, and coffer dam construction.
On-site from July 2011 to July 2012, the majority of the heavy lifting went to the Terex HC 230 crane. “It was a workhorse for us,” said Morrison.
The first task for the crawler crane was driving the piles of the Donald Bridge and work trestle. Equipped with a 130,000-lb. D160 diesel hammer, the HC230 efficiently drove 18 piles to support the 1,000 ft (300 m) long bridge. “Some of the pilings were up to 296 ft. deep,” said Morrison.
The Terex HC 230 offers a number of standard and optional features to assist with pile driving. The crane’s standard free-fall capability of the main and auxiliary drums aids in the firing process of diesel impact hammers, as well as setting the leads. “Having free-fall capability is very popular among bridge building contractors,” explains Jim Creek, senior crawler crane product manager for Terex Cranes – Americas. “Not only is free fall important for piling work, but, in some cases, clam bucket work is also needed, which makes free fall a must-have feature.”
All drums, including the optional third drum, offer a power up/down feature. For setting the piles, Flatiron’s crew used the third drum to position the piles vertically. “The crane has individual controls for separate functions, which works very well for pile driving, as the machine is using three hoist drums during the process,” adds Creek.
Each drum is grooved for heavy-duty 1.13-in diameter rope to increase maximum single line pull. “The HC230 offers a high, 54,060-lb. single line pull, which bridge contractors need for smoothly lifting heavy hammers into position and for piling extraction, if necessary,” says Creek.
Nimble Workhorse
Once the bridge and trestle piles were set, Flatiron’s crew called on the HC 230 to help assemble and position the bridge’s girders. Flatiron used 190 ft. of boom length with an offset tip and 3.8 ft. rooster sheave. The contractor equipped the crane with its maximum counterweight of 150,000 lbs. on the upper carriage and 32,000 lbs. on the lower.
A total of 84 girders, some constructed in pairs on the ground and other spliced together in position, were used to build the Donald Bridge. Crew members assembled the girders on land, and the HC 230 moved them into position. “The crane had to move them approximately 200 ft.,” says Morrison. “When maneuvering on the trestle, the operator had to cut the tracks 90 degrees in order to set the girders in place. We couldn’t do what we did without the crawler crane.”
The girder pairs were long and heavy. Morrison recalls one lift in particular that posed a challenge. “The longest pair were 138 ft. long by 9.8 ft. wide,” he said. Working at a 42-ft. radius with 190 ft. of boom, the operator positioned the 140,000-lb. girder assembly at a 79° boom angle. “We were working at about 95 percent of the crane’s capacity that day,” he added.
During bridge construction, Flatiron’s crew moved the crane back and forth across the Columbia River, and the machine’s design facilitated de-rigging efficiently. Its hydraulic counterweight removal system simplified counterweight installation and removal. Within a day, crew members had the crane de-rigged and loaded on to nine low-boy trailers, ready for transport.
“We had the crane up and down about three times for moves across the river,” says Morrison. “It’s a crane very easy to disassemble, transport, and assemble.”
Author; Unknown
Source:
http://www.cranehotline.com/articles/6086/terex-cranes-ease-traffic-in-british-columbia/