At $215 million, it’s the largest single highway contract let to date by the New York State Department of Transportation (NYSDOT). Covering only 2 mi. (3.2 km), it’s also the most concentrated. The reconstruction and rehabilitation of the northern end of the six-lane Brooklyn-Queens Expressway (BQE) in Woodside, Queens, NY, calls for demolishing and replacing 13 highway bridges and four railroad bridges, each a section at a time to keep traffic moving. Major items of work include: 7.5-mi. (12 km) lanes of new concrete roadway construction; .56 mi. (.9 km) of railroad construction; 6 mi. (10 km) of retaining walls; a 72-in. (183 cm) water main relocation; a new storm water pumping station; and approximately 900,000 cu. yd. (700,000 cu m) of excavation and fill. For prime contractor Slattery Skanska Inc., Whitestone, Queens, the contract is more like individual road jobs, because of the need to maintain traffic on the existing expressway, the adjacent rail line and neighboring streets. Peter Franco, project manager, of Slattery Skanska, explained, “When I started out doing road work, I thought it was a big deal to put up one half of a bridge, open it to traffic, then close off other roads and reroute traffic onto the new span so we could build the other half of the bridge. Now we’re doing this at least 40 different times on the BQE project.” Schedule Before the contract was let, NYSDOT estimated the job would take approximately 46 months from the start to finish for major items, under the states A + B incentive/disincentive contract formula. According to the NYSDOT, the A + B — or “cost-plus-time” — bidding procedure makes contractors responsible for developing schedules, and incentive/disincentive clauses. They reward or penalize contractors for coming in ahead of or behind schedule. Bidders estimate how long a project will take to complete and multiply the number of days by a daily user cost, which NYSDOT calculates using a computer model. That figure, B, is added to the bid for the work itself, A, and the award goes to the lowest total bid. For the B part of the contract, Slattery Skanska bid 40 months, actually 1,217 days, for completion of the major work. The user cost is $10,000/day, which is the incentive payment for early completion and the penalty for coming in late. There’s a cap of 156 days on the incentive portion but none on the disincentive. Plus, unlike some recent large NYSDOT A + B contracts, there are no interim incentive milestones for early completion of parts of the project — it’s hit the final day on or before, or face the penalties. However, said Franco, “We have our own internal, built-in milestones on the project which we developed using the critical path method.” Slattery Skanska is on track to finish in the spring of 2004, having easily passed the 50-percent mark in early summer of 2002. Franco said the company is working only one shift a day, although there’s a lot of night work because there’s less traffic then. Traffic control is one of the determining factors of the job: there must be six lanes open for traffic during morning and evening peak hours, without detouring onto local streets, and NYSDOT has strict rules governing lane closures at other times. The objective is to minimize the impact on and inconvenience to motorists. While this contract is formidable, Slattery Skanska combines more than a century of experience in heavy construction. Two other Skanska USA companies are involved in the BQE job. Underpinning and Foundation Constructors Inc., Maspeth, Queens, is drilling the augered soldier piles, cast-in-place concrete pipe piles and miscellaneous timber piles. Koch Skanska Inc., Carteret, NJ, is managing the superstructure steel procurement, fabrication and erection. Slattery Skanska also brought in Bi-County Paving Corp., Farmingdale, NY, to help with the final grading and do the paving. Area Profile Geographically, the job extends from Broadway to 25th Avenue and the Grand Central Parkway. The highway runs through a heavily populated residential and light industrial neighborhood, as well as straddling St. Michael’s Cemetery. The job is a complex combination of vertical and horizontal realignment of lanes and grades on the highway and connecting streets; widening of the mainline roadway and ramps to permit 12-ft. (4 m) wide travel lanes; construction of a new single-point-urban-interchange at the exit for Northern Boulevard; and relocation of the CSX rail line which coexists in the same right of way with the highway. In some areas, the roadway is being lowered to provide the necessary 15-ft. (4.7 m) clearance for underpasses. New shoulders, drainage, retaining walls, lights and signs also are being provided. Built approximately 40 years ago, this section of the BQE is one of the most heavily traveled in the country —NYSDOT estimates 120,000 vehicles a day — and it has deteriorated with age. Because it was designed prior to the development of the Interstate Highway system, the BQE was plagued with design flaws. Sharp curves, lack of shoulders, short acceleration and deceleration ramps, and confusing left-exit configurations were characteristics of the pre-Interstate era expressway. “This highway was originally built alongside the right of way of the CSX rail line,” Franco said, “because many residences and businesses were already here. At that time the rail line was much busier, so the highway was designed to weave in and out and under and over the rail line and existing streets. Now, we are reversing that scheme, by straightening out the expressway so that the rail line weaves around it.” In addition, Slattery Skanska is lowering the grades on intersecting streets. Statistics Quantities on the job include: 468,000 cu. yd. (360,000 cu m) of excavation and 403,000 cu. yd. (310,000 cu m) of backfilling; 52,000 cu. yd. (40,000 cu m) of concrete demolition; 39,000 cu. yd. (30,000 cu m) of concrete paving; 29,000 cu. yd. (22,000 cu m) of concrete for 18,000 linear ft. (5,400 linear m) of retaining wall construction; and 20,000 cu. yd. (15,000 cu m) of footings. Franco said that he considers excavation as separate cut and fill items. “We’re basically limited to the footprint of the expressway and rail line. If we’re going to use excavated material as fill, we have to do it immediately. There’s almost no room to stockpile it on site for later use. So, we have to balance the expense of hauling it away and stockpiling versus selling it. In a way, that’s a little unfortunate. We uncovered some really good material in the rail embankments,” he said. Bridges Highway and railroad bridge foundations are supported by driven piles and reinforced concrete-filled drilled shafts ranging up to 10 ft. (3 m) diameter and 90 ft. (27 m) deep. Wide-flange soldier beams socketed in concreted 3-ft. (1 m) diameter drilled holes support the retaining walls. The bridges represent most types currently in use: wide-flange steel, steel plate girder, steel trapezoidal box girders and prestressed and post-tensioned concrete box beams. The longest is a trapezoidal box beam steel unit which will carry the new BQE 230 ft. (70 m) over Northern Boulevard. An adjacent 200-ft. (60 m) steel truss bridge is being built for the CSX line. Equipment Cranes play a vital role in bridge construction and the company is using cranes from the largest all-terrain units to cherry pickers and aerial work platforms, many from JLG. The principal large cranes, hydraulic truck-mounted and all-terrain, include: Grove GMK 5175, 175 ton (158 t); Krupp KMK 5110, 110-ton (100 t); Demag AC 535, 200 ton (180 t), Liebherr LTM 1400, 440 ton (400 t and LTM 1225, 250 ton (225 t) and Tadano units. A Link-Belt 150-ton (135 t) lattice-boom truck crane also is being used. Caterpillar and Komatsu hydraulic excavators are the workhorses on the job because of their versatility. In addition to digging buckets, they can be outfitted with breakers, compactors and hooks. Utility equipment on the project includes Caterpillar tractor-loader-backhoes and wheel loaders. In addition, Slattery Skanska also is using a Bauer drilling rig for the retaining wall pilings, while Underpinning and Foundation is using two Junttan Soil Mac rigs to dig the larger drilled shafts for the bridges. Paving According to Franco, most of the new concrete paving of main lanes and ramps will be a European design: a 12-in. (30.5 cm) unreinforced top layer, a 4-in. (10 cm) permeable low-sand “popcorn” base formulated for quick drainage, and a 12-in. (30.5 cm) subbase for a total of 28 in. (71 cm) depth. There are doweled joints every 12 linear ft. (3.6 m) on the top layer. Because Slattery Skanska has to work pavement joints in with working lanes to keep traffic moving, crews use steel forms and screeds. Environment Fortunately, there are a minimum of environmental concerns since Slattery Skanska is operating almost entirely within the existing highway and rail line footprints. During construction, Slattery Skanska adheres to restrictions on noise and vibration. The New York City Department of Environmental Protection (NYCDEP) is working in conjunction with transportation officials to reduce air pollution by planting trees and other vegetation along the expressway. The tree-planting project also will mitigate the visual and noise impact of heavy vehicle traffic on area neighborhoods. When completed, the new northern terminus of the BQE will be transformed from one of the oldest urban expressways in the country to the newest, in terms of highway technology in bridges and paving. It also will help to alleviate chronic traffic jams and associated aggravations, both on motorists and residents.
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