ACTT Interim Report
Texas Department of Transportation (TxDOT)
September 9-11, 2003, Dallas, TX
Project Pegasus, a $760 million project located at the southern edge of downtown Dallas, now in the planning phases, involves the total reconstruction of the I-30/I-35E interchange (the "Mixmaster"), as well as other portions of both highways. The project covers 17.7 km (11 mi) of roadway and more than 99 entrance/exit ramps. The roads to be rebuilt cross four active railroads, including the DART Light Rail, which is to remain in operation while all of the bridge structures spanning the railroad are replaced. Historic landmarks are also a concern, such as a 609.6-m (2,000-ft) historic concrete arch bridge that is to remain in place during construction. Neither I-30 nor I-35E has been substantially improved since original construction in the early 1960s, so dramatic changes will be necessary to comply with current design guidelines and to accommodate current traffic patterns and volume. Significant coordination challenges are expected to arise with various stakeholders, such as DART, North Texas Tollway Authority, the City of Dallas, Dallas County, and the North Central Texas Council of Governments. Additional project information is available at http://www.projectpegasus.org/.
- Construct the Trinity Parkway (paralleling I-35 on the south side and in the program) ahead of schedule, so that it can be used as a detour during construction.
- Employ construction techniques for structures that minimize the traffic impact, such as incremental launching, lateral slide, and heavy lift methods.
- Develop an onsite plant to minimize time and congestion.
- Maximize use of partial road closures for better contractor mobility.
- Set up a dedicated incident management system to quickly locate incidents throughout the project site.
- Delegate broader decisionmaking authority to the Dallas District for accelerated response purposes.
- Use contractor incentives to minimize traffic disruption.
- Launch intensive media efforts to inform residents about upcoming changes.
- Use design-build contracting.
TxDOT's overall evaluation of the workshop confirmed there is significant potential to reduce the construction time to 4 years from the original estimated construction schedule of 7 years. TxDOT will now be evaluating the reports produced by the Skill Set groups and deciding which ideas should be implemented in the future planning, design, and construction phases of Project Pegasus. Follow-up meetings with TxDOT will be conducted to evaluate the long-term benefits of the workshop. Detailed workshop report is available at http://www.fhwa.dot.gov/construction/.
New Jersey Department of Transportation (NJDOT)
July 22 and October 27, 2003, Trenton, NJ
NJDOT is planning to improve the westbound structure of Overpeck Creek Bridge on Bergen County's Rt. 46. The bridge is located next to the New Jersey Turnpike and is only 8 km (5 mi) west of the George Washington Bridge leading into New York City, so minimizing the impact of construction on the traveling public and completing the work as soon as possible is vital. NJDOT's original plans called for the total replacement of the westbound superstructure, which was deemed cost-effective (at an estimated $10 million), but would impose 18 months of traffic disruptions. Hoping to reduce the projected construction time, the NJDOT decided to consult with the ACTT team.
- Close the westbound structure completely.
- Make use of precast elements such as double I-girders, deck bulb tee, precast box beam, adjacent bulb tee, inverset modular bridge deck units, and concrete/steel beams with a full-depth precast deck.
- Utilize lightweight high-performance concrete (HPC) to reduce deadload.
- Employ polymer concrete for joint closures.
- Use fiber-reinforced polymer composites for the deck.
NJDOT decided not to replace the entire superstructure or use road closures, but to use prestressed, precast HPC (EFFIDECK) for a new bridge deck to expedite construction. NJDOT will also replace some of the bridge's secondary steel beams, while maintaining the bascule span steel main girders. Work to replace the bridge deck and floor beams is under design and expected to begin early next year, and last 3 months, at an estimated cost of $3 million. The improvements will be carried out while maintaining two lanes in the westbound direction at all times. As a result of ACTT's assistance, NJDOT has decided to call upon the team's help for a much larger $250 million project, the reconstruction of the I-295/I-76/Rt. 42 interchange.
California Department of Transportation (Caltrans)
December 9-11, 2003, Ontario, CA
Caltrans conducted an ACTT workshop with the goal of applying accelerated construction principles to the planned French Valley Parkway Interchange on I-15. This project consists of a new interchange at French Valley Parkway on I-15 in the cities of Temecula and Murrieta, Riverside County, CA. Due to the fast growth of this region, the existing interchange and the local roads are very congested, with traffic accident rates exceeding state averages.
- Modify the design in order to eliminate two bridge structures and braided ramps.
- Pave the median to use as a detour during construction and provide for future HOV lanes.
- Prefabricate the entire bridge span on site and roll, launch, or lift into final position to drastically reduce construction time and minimize traffic disruptions.
- Make the contractor responsible for the traffic control and management, but have Caltrans be responsible for quality control/quality assurance. This should be incorporated into the contract specifications.
- Explore alternative revenue streams such as tax increment financing, a city or regional transportation tax, truck toll lanes, and special assessments.
- Include utility design and utility coordination in the design/construction contracts.
- Dedicate a Caltrans Utility/Right-of-Way expert to guide and assist the design and construction teams.
- Solicit contractor input during design or preconstruction through AGC review, mandatory pre-bid meetings, and constructability reviews.
- Employ demand management techniques such as transit incentives during the construction.
- Provide dedicated freeway service patrols (FSPs) and incident response teams.
- Clearly define incident management roles and responsibilities during project planning and design based on types of incidents.
In addition to alleviating congestion, the project's goal is to provide additional access for the local communities, whose many residents currently travel long distances to places of employment.
Louisiana Department of Transportation and Development (LDOTD)
December 15-16, 2003, West Monroe, LA
At a limited (Structures, Construction, and Traffic/Safety/ITS skill sets) workshop hosted by LDOTD in December, the focus was on the rehabilitation of a 40-year-old section of I-20 in Monroe. The route passes through Monroe just south of the original downtown area on a 2.9-km (1.8-mi) section of elevated highway that includes the spans crossing the Ouachita River. The elevated section of I-20 has remained in service with routine maintenance and only one major rehabilitation since 1965. The designers soon realized that the current traffic volumes and lack of realistic detour routes would create gridlock within the area highway system, including the Interstate. As plans for the project progressed, traffic control considerations became the greatest challenge. LDOTD had developed guidelines to minimize motorist delay and time spent on construction, but the project site and required work did not seem compatible with achieving those goals.
- Completely close the Interstate to traffic at night and provide for two lanes of continuous flow traffic to detour from I-20 onto local streets. Allow I-20 lane closures only at night.
- Ensure prior completion of nearby projects to ease traffic flow. At the time of the workshop, the project was scheduled to undergo construction concurrently with some other area projects.
- Restrict all Interstate traffic detours to the roadway network adjacent to the Interstate, avoiding Interstate traffic detours to other Ouachita River crossings.
- Modify traffic signals on other river crossings to allow for dynamic traffic flows.
- Implement an aggressive incident management system, including performance- based wrecker service.
- Use a smart work zone with cameras, variable message signs, and advance warning signs.
- Extend the limits of the project to perform all needed rehabilitation at one time.
Many of the workshop's recommendations centered around performing all needed rehabilitation at one time, thus avoiding multiple disruptions of traffic over several years and forestalling more serious measures being required to restore the deck surface.
Montana Department of Transportation (MDT)
January 26-28, 2004, Missoula, MT
For this ACTT Workshop, participants spent three days focusing on inventive ways to hasten construction on a 90-km (56-mi) stretch of US Highway 93. This corridor is unique in that it crosses a portion of the Flathead Indian Reservation, which is home to the Confederated Salish and Kootenai Tribes (CSKT). The corridor also crosses several animal migratory routes and waterways as well as the Ninepipe National Wildlife Refuge. The guiding philosophy for modification of the roadway throughout this corridor is to protect the cultural, aesthetic, recreational, and natural resources located along the corridor.
- Establish a corridor management/communication team to include all three governments with a single-point-contact speaker.
- Change the sequence of project construction to allow for a more efficient use of resources.
- Employ such construction methods and materials as jet grouting, welded wire walls for wall facings, and controlled staging of geotech work. Utilize contractor staking and predetermined pay quantities. Accommodate and encourage GPS grade control.
- Use prefabricated structural components and install them at night. Due to short construction season, prefabricate structural components during off-season.
- Pre-approve tribal borrow sites to minimize inspection time during construction.
- Establish a comprehensive traffic management plan, including considerations such as pedestrian traffic control, elderly drivers, property access, wildlife concerns, and regular coordination meetings.
- Allow contractors to bid with an option for traffic control/sequence of operation.
- Employ Transportation Demand Management techniques to reduce the number of vehicles on the roadway resulting from local commuters.
- Create a database accessible by all entities to track Right-of-Way/Utilities progress. Make automated acquisition forms available.
It is hoped that these recommendations will help reduce construction time from 5 years to 3 years. The ultimate goal is to design a safe and efficient road that is sensitive to the environment and context of the area.
Washington Department of Transportation (WSDOT)
March 16-18, 2004, Seattle, WA
A March workshop hosted by Washington State DOT (WSDOT) was devoted to an SR-520 project between I-5 and I-405 in Seattle that will include the replacement of a 40-year-old floating bridge across Lake Washington. In addition to inadequate capacity (designed for 6,500 ADT, but now handling 120,000 ADT), this structure presents other concerns such as vulnerability to storms and earthquakes. Additional information on the existing structure was available at ftp://www.wsdot.wa.gov/wsdot/projects/translake/ftp2/scoping/bdEGBridge.pdf. The cost of this project will be between $1.5 and $3.4 billion, depending on WSDOT's selection of the number of lanes for the new facility, making this the largest ACTT project to date.
- Use Self Consolidating Concrete (SCC), particularly for the construction of the pontoons. The great depths of the pontoons and the large quantity of concrete required would make use of conventional concrete very labor intensive. Contrary to conventional concrete, SCC flows easily and fills all cavities, thus eliminating the need for vibration which could harm previously placed concrete.
- Shorten overall project delivery time by overlapping design and construction contracts.
- Design the simple pontoons first so construction may begin while the more complex pontoons are still being designed.
- Look at segmenting contracts, such as for the replacement of the Evergreen Point Bridge, which could be completed in four segments.
- Break pontoon fabrication into separate contracts depending on type.
- Issue a separate contract for anchor system fabrication, looking at other anchor types, such as suction piles.
- Consider installing the anchor system before the pontoons arrive.
- Maximize use of the graving dock for pontoon construction through double shifts or another facility.
- Consider a temporary roadway transition span on the south side of the road, using the old bridge as a working stage and then demolishing the old bridge as work progresses.
- Establish Risk Management Teams with decisionmaking authority to undertake proactive risk assessment and management.
- Remove juvenile salmon from the work area by placing curtains between islands to keep the salmon away.
- Set up a regional traffic model and look at staging options to consider the impact of other projects in the area.
- Utilize design/build with performance specifications for lids and structures, keeping in mind that fewer lids will shorten construction.
At the close of the workshop, it was agreed that the suggestions presented could reduce construction time by as much as 1/3.