Paving the Way Toward Completion

T-REX faces paving challenges and traffic shifts this summer

by Karl Lueders

The majority of the paving on T-REX will be completed by the end of the summer, and light rail testing has also begun between University and Broadway through the Narrows.

Construction along Denver's Transportation Expansion Project is moving toward the home stretch, with the completion for work on Interstates 25 and 225 and the light rail system still set for fall 2006. But contractors still face several major challenges through this summer and fall.

This summer marks the final paving year for the highways, with more than 50,000 cu yds of concrete and 200,000 tons of asphalt yet to be laid, said Bill Murphy, project manager for Southeast Corridor Constructors, the T-REX general contractor.

"The northbound Narrows [the stretch of I-25 between University and Broadway] is our main focus for paving," he said.

While Murphy expects the majority of the paving to be completed by the end of the summer, the project schedule has extra time built in to compensate for uncooperative weather.

"The stone-matrix asphalt we use for the final lift [the final two-in. topcoat] is more susceptible to the weather than standard asphalt," Murphy said.

The stone matrix must be poured when the ambient temperature is above 50 degrees. And, since paving is done at night, the majority of the stone-matrix paving will likely be done over the summer. "If we pour the concrete and it gets cold," Murphy said, "we have to heat and cover it, which just adds cost to the project."

advertisement

University Avenue

University Avenue will be a significant traffic bottleneck around the highway this summer, as the interchange at I-25 and University will change from its temporary diamond layout to a single-point urban exchange.

"One of our biggest challenges over the next six months will be reducing University to one-plus-one lanes," said Larry Warner, T-REX project director. "That started in April and will go through fall of 2005."

Milestones

In January, T-REX released a statement citing 10 of the major milestones it would achieve in 2005. One of the 10, the Elati Light Rail Maintenance Facility, became operational in January and the first T-REX light rail vehicles arrived the same month. Light rail testing has also begun between University and Broadway.

One of the major projects on the T-REX list still under way but nearing completion is the I-25/I-225 interchange, which SECC has slated for completion this summer. Warner said that congestion at the interchange was alleviated with the addition of another lane on the southbound I-225 ramp in February.

"From the traveling public perspective, opening the southbound I-225 ramp eased the bottleneck. With the one-lane configuration, there was a grade that forced trucks to gear down to get to I-25.

Completion of the Colorado and Hampden bridges, slated for later this spring, will be a watershed mark for T-REX," Murphy said. "After we finish work on the Colorado Boulevard bridge, there shouldn't be any other girder erections on T-REX."

Another 2005 goal for T-REX is the continued construction of the Lincoln Avenue parking garage. According to Warner, the vertical retaining walls are up and 1,100 of the 1,700 concrete structures have been cast to be fitted at the site.

Light Rail Work

Before power can be run to the trains, SECC has to shift I-25 to its final location. Murphy said he expects that upon completion of paving, they'll be able to move quickly on to the final portions of the light rail project.

"By the end of this year, we expect to have the entire overhead contact system and ballast in place," he said. "Then we can tie the power sources into the light rail."

By September 2006, the contractors need to have completed integrated testing on the entire light rail system and be ready to turn over operations to RTD for its pre-revenue testing. The light rail line is scheduled to open in December 2006.

Click here for more Features >>