Bridge move a sure thing for Saturday, RTD says
The span sits complete before its slow move across West 6th Ave.
LAKEWOOD – FasTrack’s light rail bridge rollout is on for Saturday along with the complete closure of a significant stretch of West 6th Avenue.
“We are on and we are moving forward and have closed the on-ramp,” said Brenda Tierney, spokeswoman for the Regional Transportation District, referring to Friday’s midday shutdown of the ramp from Union Boulevard to eastbound West 6th Avenue.
“We won’t turn around at this point,” Tierney added.
After snowy weather forced a postponement in last weekend’s original roll-out plan, Tierney said, FasTracks crews will move will roll the main span of the West Corridor light rail project’s signature double-track bridge across the busy highway just east of the Simms/Union interchange this weekend. All of the highway between Simms/Union and Kipling Street close at 8 p.m. Friday and will remain closed until about 5:30 a.m.
The Frontage Road north of West 6th also will be closed.
The bridge is expected to start moving early Saturday morning.
Construction crews have spent the past several months assembling the tied-arch, weathered steel bridge just south of and will move the span to its final position over the highway aboard a “dolly” made of two eight-axle, 35-foot platforms. The bridge will slide over guided rollers pushed by hydraulic rams capable of producing as much as 270,000 pounds of force per square inch.
The rollout, at speeds from 10 to 25 feet per hour, is expected to take up to 30
hours, according to Tierney.
Although the move will be far from a NASCAR-pace, RTD is installing bleacher seats for public viewing at nearby Lakewood Fordland, on the northeast corner of Quail Street and the 6th Avenue Frontage Road. The bleachers will be available to spectators between 9 a.m. and 4 p.m. Saturday.
“That’s the only ‘formal’ day, the only day we will actually have bleachers out there and information and people from RTD there to answer questions. But we have leased the parking lot for the whole weekend. So if people want to drop by on Sunday and just stand there and look, that’s fine,” Tierney said.
The bridge is expected to reach it’s resting spot sometime between midnight Saturday and 6 a.m. Sunday morning.
“Sunday, they (crews) will spend cleaning up the highway and attaching the bridge to the other side,” Tierney said.
While spectators are likely to be impressed by the lumbering move, drivers probably will be grumbling throughout the weekend.
Major congestion can be expected along the detours – Kipling north to West Colfax Avenue then west to Simms and south back to West 6th for westbound traffic; and Union Boulevard south to West Alameda Avenue, then Kipling north to the highway for eastbound traffic.
Folks headed to or from the mountains and foothills also can take Interstate 70 westbound to avoid the detours.
The bridge is a “clear span” design with no center pier in the freeway median to hold up the span. Instead 44 cables strung from the arch to the base provide support with an estimated breaking strength of 688,000 pounds. There are 1,950 feet of 23/8-inch cable criss-crossing the bridge.
The clear-span design will be wide enough from side pier to side pier to allow future widening of the freeway, the Simms-Union interchange ramps that pass beneath the bridge and the frontage road on the north side of West 6th Avenue.
It is one of only two or three clear-span bridges in the U.S. The design allowed it to be assembled, then moved into place instead of being put together in-place.
The bridge is 286 feet long, 43 feet wide and is 65 feet tall from crown to base. Its structural steel components weigh a total of 1.2 million pounds. The high-strength steel is “weathered”, turning brown as a “protective oxide coating” forms, eliminating the need for painting according to a fact sheet distributed with the FastTracks memo.
The bridge is a “clear span” design with no center pier in the freeway median to hold up the span. Instead 44 cables strung from the arch to the base provide support with an estimated breaking strength of 688,000 pounds. There are 1,950 feet of 23/8-inch cable criss-crossing the bridge.
The clear-span design will be wide enough from side pier to side pier to allow future widening of the freeway, the Simms-Union interchange ramps that pass beneath the bridge and the frontage road on the north side of West 6th Avenue.
If the bridge had been built in place over 6th Avenue, the project could have forced months of traffic nightmares.
“This approach to bridge construction enabled West Corridor crews to
work in a safe environment outside of traffic and significantly minimize impacts to commuters using the 6th Avenue freeway,” according to an RTD statement.
“If the bridge had been constructed in place over the highway, we would have had to impact traffic on 6th Avenue many times over the course of construction instead of just one weekend as we are doing,” said Jim Starling, RTD’s West Corridor Project Manager. “But safety is always the utmost priority.”
and weather permitting, we will move forward with the operation this weekend.”
The 12.1-mile West Corridor light rail project is RTD’s first FasTracks project under construction. The line will link Union Station in downtown Denver with Lakewood, the Jeffco government complex in Golden and the Federal Center. It is expected to be in operation by 2013.
