Triangle Grading and Paving, based in Burlington, NC, recently began on-site preparations on a new $1.5- million, three-lane bridge and road project that will cross over the Northeast Creek, on Alston Ave., in western Durham County, NC.
The new bridge will replace a 30-year-old, two-lane asphalt bridge built on pre-stressed concrete channels, and supported by reinforced concrete caps on timber piles.
According to Eben Miller, North Carolina Department of Transportation (NCDOT) assistant resident engineer, the poor condition of the old bridge and a sufficiency rating of 6 percent, contributed to the need of replacing the bridge.
“In addition,” Miller said, “increased traffic due to its location in the Research Triangle area prompted the need for a third lane to the bridge.”
Triangle Grading and Paving will handle the approach, grading, paving and drainage work, and will install guardrails; however, D.W. Lyle Corporation of McKenney, VA, was subcontracted by Triangle Grading and Paving to demolish the old bridge and construct the new one.
Bridge construction was to begin April 1, but has been delayed until later in the month because of utility relocation delays, said David Lyle, executive vice-president of D.W. Lyle Corporation.
Miller added, “A tremendous number of conflicts have occurred during the on-site preparations. The main reason for the holdup is due to the eight utility companies in the project area, with either overhead or underground facilities that needed to be relocated.
“In particular,” he noted, “the five companies with numerous underground fiber optic lines have had the most difficulties. Consequently, there has been a delay in getting construction started.”
Lyle said, “Construction of the bridge will occur in two phases. The first phase will be to construct two lanes and one sidewalk. During the second phase, the traffic will be shifted to the new bridge; the old bridge will be dismantled and recycled on site or hauled to a waste/recycling facility. Then the bridge will be completed to its final width, adding the third travel lane and one sidewalk.”
The new bridge will be a 105 ft. (32 m) long and 60 ft. (18.2 m) wide to accommodate three travel lanes and sidewalks on both sides. The bridge substructure includes drilled shaft interior bents, driven H-pile end bents, and the superstructure will employ standard NCDOT cored slabs with an asphalt-riding surface.
“Standard equipment will be used in the demolition of the old bridge,” Lyle said.
This includes an Hitachi 200 excavator with a Tramac demolition hammer, a John Deere 892E-LC excavator with a JRB rotating jaw crusher, and a Link-Belt LS-108B crawler crane.
Gemini Drilling and Foundation LLC, Kernersville, NC, was subcontracted to provide construction of 3-ft. (1 m) drilled shafts averaging 26 ft. (7.9 m) deep at six locations.
According to Dena Casper, Gemini project manager, a 92,000-lb. (41,730 kg) Watson 3100 drill rig will be used to drill piers/caissons for the bridge.
“The NCDOT reviewed the drilling equipment and plan of operations to ensure strict adherence to project plans and specifications,” Miller said. “NCDOT also reviewed the proposed pile hammer to determine if proper bearing capacity would be achieved without overstressing or damaging the steel H-piling [furnished by Skyline Steel of Raleigh, NC].”
Once the foundation work is complete, reinforced concrete pile caps will be built on the drilled shaft and H-pile foundations, and the pre-stressed cored slabs will be put in place. The bridge superstructure will require 2,050 linear ft. (624.8 m) of 3 ft. by 2 ft. (1 by 2 m) pre-stressed cored slabs supplied by Eastern Vault of Princeton, WV.
All reinforcing steel has been subcontracted to National Erectors, of Lumberton, NC, and the ready mix concrete supplier for bridge construction is Chandler Concrete Company.
New 1,000-ft. (304.8 m) approaches will be constructed on both the south and north side of the bridge. The new approaches will increase from two to three lanes and will be topped off with asphalt –– 1,400 tons (1,270 t) of base, 1,700 tons (1,542 t) of intermediate, and 1,300 tons (1,179 t) of surface.
According to Miller, the project will require 650 cu. yds. (497 cu m) of unclassified excavation and 10,000 cu. yds. (7,646 cu m) of borrow excavation.
“This Northeast Creek bridge project is quite standard construction and should progress without problems,” Lyle said. “The only unusual aspect of the bridge project will be dealing with a transmission power line overhead that limits the maximum height of equipment.”
Completion of the bridge is set for Aug. 15, 2005.