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Highway Quality Compendium
The Future Is Now
by Kathleen Bergeron
These snapshots of successful projects from around the country show that the stage is set for a new approach to highway design, construction, and maintenance.
In this issue, several articles pose a "what if" question about a new vision for highway development. The approach envisions the construction of long-lasting roads using innovative technologies and practices to accomplish fast delivery of efficient and safe pavements and bridges. But is this approach easier said than done? Are there examples out there now, demonstrating what is possible?
State departments of transportation (DOTs) and their partners already are implementing many projects employing one or more innovative approaches or technologies. And these examples are not all mega-budget projects; several cost only a few hundred thousand dollars to complete. Nor are they all emergency projects executed in response to crisis situations. Clearly, emergencies represent unique situations where highway officials set aside the need to hold lengthy public hearings and develop numerous design options because of the necessity of getting a facility back into service quickly.
The following examples demonstrate the diversity of ongoing projects. And they are not limited to one or two States but are scattered throughout the country.
Alabama Employs Incentives to Replace Bridge
On January 5, 2002, a loaded gasoline tanker traveling north on Interstate 65 (I-65) within the I-20/I-59/I-65 interchange in Birmingham, AL, crashed and burned under the I-65 southbound bridge. The fire caused the steel girders of the main span over southbound I-65 to sag about 3 meters (10 feet), which required closing both northbound and southbound I-65. Removal of the damaged bridge began as soon as the wreck was cleared, and northbound traffic was restored on January 6. The road user cost resulting from closure of the southbound bridge was estimated at $90,000 per day.
The department designed a new concrete girder bridge and awarded the contract on January 16; construction started on January 21. The contract allowed 90 days for completion of the new bridge with an incentive/disincentive provision of $25,000 per day. The successful bidder completed the new bridge in 37 days, earning a $1,225,000 incentive. The contract cost, including the incentive payment, was still less than the cost proposed by the second bidder.
"Within 53 days, the damaged bridge was removed, the design completed, and a new bridge built, demonstrating intense commitment and cooperation among all parties involved-especially State engineers, the concrete fabricator, and the contractor that built the new bridge," says Division Administrator Joe D. Wilkerson with the FHWA Alabama Division.
Alaska Upgrades 18 Bridges With Precast Concrete
Deadhorse, AK, is located on Prudhoe Bay, where the Alaska oil pipeline originates in the North Slope oil fields. Although the 668-kilometer (415-mile) Dalton Highway has an average daily traffic count of only 250 vehicles, the highway is critical to Deadhorse because it is the only road connecting the community to the outside world and carries all supplies for the oil field. In 1992, the Alaska Department of Transportation & Public Facilities began replacing the timber decks with precast concrete slabs on 18 bridges on the Dalton Highway between Fairbanks and Deadhorse. Instead of continually replacing the timber decks every 8 years, the agency decided to use precast concrete panels that would last for approximately 50 years, resulting in savings in the cost of replacing the timber decks and in recurring impacts on the traveling public.
During reconstruction, the timber decks were replaced with full-width precast concrete slab units. Through negotiations with the trucking and tour bus companies, the department agreed that the road could be closed completely to traffic for 12 hours each day. During this period, the contractor removed sections of the old timber deck, welded new shear studs to the top flange of the steel girders, placed the precast slab units (which had block-outs to accommodate the new shear studs), placed quick-setting mortar in the block-outs, and then reopened the road to traffic. This process continued until each bridge was completed. The construction technique enabled the department to redeck the bridges in approximately 7 months, with minimal impact on truck traffic.
Arizona Uses Innovative Bidding for HOV Project
The Arizona DOT is widening SR-51 (Piestewa Freeway) between I-10 and Shea Boulevard in Phoenix, AZ. Adding high-occupancy vehicle (HOV) lanes in each direction will make a direct connection to the existing HOV lanes on I-10 at the south end of the project, representing a substantial extension of the HOV concept in the Phoenix metropolitan area. The connection to I-10 provides a smooth and efficient link between HOV lanes on the intersecting freeways.
"Such linkages have been a major challenge for highway engineers across the country," says Ken Davis, a senior engineering manager with the FHWA Arizona Division. "With the additions of this project, drivers will have no need for extensive lane changing to transition from HOV lanes on one freeway to HOV lanes on another freeway."
The project employs a design-build contract and includes the A+B bidding (cost plus time) concept as well. Together, these two contracting methods have fostered considerable innovation and creativity in tackling this major freeway expansion in a confined corridor, while substantially reducing the length of construction (only 330 days instead of the 480 days originally anticipated) and the extent of traffic disruption. Full-weekend closures are enabling the contractor to make maximum progress during periods of lower freeway usage. In addition, the project incorporates substantial intelligent transportation systems (ITS) features and enhances the Freeway Management System in the Phoenix metro area.
The project also provides an asphalt-rubber friction course surface (quiet pavement) throughout-in part to hide existing pavement joints and facilitate relocating lane markings, but also to provide an additional measure of noise mitigation. "This is a very significant feature-the adjacent neighborhoods have complained for years about this freeway's high noise levels," Davis says.
California Repaves a Major Freeway
Interstate 710 is 46 years old and heavily traveled, averaging 157,000 vehicles per day, with one of the highest concentrations of deteriorated pavements in California. Trucks carrying cargo from the ports of Long Beach and Los Angeles account for 13 percent of the freeway's total traffic, but the original design a half century ago assumed that only 5 percent of the traffic would be trucks. Although the California Department of Transportation (Caltrans) patched the road at various locations during its lifetime, the agency never had implemented a rehabilitation project by separate contract.
A recent Caltrans rehabilitation project on I-710 between State Route 1 and I-405, just north of Long Beach Harbor, CA, involved applying long-life asphalt pavement with a life expectancy of 30 to 35 years. A task force on long-life pavements at Caltrans has been working since 1998 on this showcase project, which breaks tradition with how the department usually constructs freeway paving projects. The task force includes members from the asphalt concrete industry and the University of California at Berkeley's Pavement Research Center. "We're enthusiastic about this pilot project testing new, longer-lasting asphalt paving methods," says Doug Failing, director of Caltrans District 7. "This is the first time these creative asphalt paving methods have been used on a California freeway."
The project employed an innovative traffic management plan that consisted in part of using a traffic staging plan involving freeway crossovers. During this critical stage, Caltrans employed eight 55-hour weekend closures that enabled the department to shut down one direction of the freeway for construction while traffic was detoured to the other side using movable barriers. This made it possible to provide two open lanes of traffic in each direction throughout the extended weekends. The project also provided motorist information strategies such as an incident management program, an elaborate public awareness campaign, and the use of more than 40 permanent and portable changeable message signs.
In 2003, the project won a Roadway Work Zone Safety Awareness Award in the category of Innovative Technologies (Methodology-Large Project) from the American Road & Transportation Builders Association (ARTBA).
Colorado Constructs Major Multimodal Project
The Colorado DOT used a design-build contract for the $1.2 billion Transportation Expansion Project (T-REX), a transit and highway project in the Denver metropolitan area, leading to significant savings in time and cost. By combining light rail, highway, bike, pedestrian, and other transit options, T-REX represents a multimodal approach to addressing traffic problems. Packaging the project into a single design-build contract creates economies of scale and significant cost savings because construction can begin before the final design is complete. The combined packaging also allows for more innovations in design and construction techniques, creating further cost savings.
Innovations in construction resulted from the latitude afforded the contractor. Retaining walls, for example, were constructed at the right-of-way using drilled caissons, which later were exposed on the roadway side and covered with fascia panels-precast concrete panels that give the appearance of a concrete wall when the actual retaining wall is formed by shoulder-to-shoulder caissons. This technique enabled the contractor to construct the wall before excavation was complete. Normally, to widen the highway in a section where the roadway is below the surrounding ground, the excess material would be removed and a retaining wall would need to be constructed. Under the design-build contract, construction of the wall commenced immediately with the drilling and placement of caissons, and excess material was removed when access became more favorable. The use of caissons, instead of a retaining wall and footing, also allowed for a smaller wall construction area.
Connecticut Installs Bridge Overnight
To minimize disruption to train service and eliminate the difficulty of building a bridge over active rail lines, the Connecticut DOT specified that a portion of the Church Street Bridge in New Haven, CT, be completed in a single night operation over a weekend. After months of building the structure alongside the active lines of the New Haven Interlocking and Rail Yard, the contractor lifted and set the bridge into place at 2:30 a.m. on Sunday, May 4, 2003.
The bridge span, a 97.5-meter (320-foot) truss weighing more than 771 metric tons (850 tons), is the main segment of the 390-meter (1,280-foot) bridge. The new bridge and roadway extension will connect New Haven's Union Avenue with Sargent Drive and provide an alternate route for traffic heading to the downtown, Sargent Drive, and Long Wharf areas of the city.
This was the first time that the Connecticut DOT built a structure offsite and lifted it into place using the largest mobile, land-based, and high-capacity crane in existence. The crane was delivered in more than 200 tractor-trailer loads of parts and required more than 4 weeks to assemble. The crane lifted the entire truss span more than 20 meters (65 feet) into the air and carried it more than 30 meters (100 feet) toward the tracks, where the span was set in its final position. The Connecticut DOT estimates that this accelerated construction method saved approximately 1 year on its overall contract time.
Florida Uses Design-Build Process and Unique Work Zone
After a series of crashes involving fatalities in the spring of 1999, the Florida DOT (FDOT) funded a project to widen the Panasoffkee Creek Bridge, carrying I-75 through Sumter County. The existing structure featured two lanes in each direction with 0.9-meter (3-foot)-wide inside and outside shoulders.
The project involved widening the existing bridge to accommodate a six-lane facility, with standard shoulders and bridge railings. The project also included upgrading the acceleration lane for the interchange at County Road 470, which required widening the approach to the northbound I-75 bridge by 244 meters (800 feet) to improve the safety of the merge area. The challenge was to widen the existing bridge by closing the 16.5-meter (54-foot)-wide median without interfering with the high volume of traffic on I-75.
"Major goals for the project were to provide a safe work zone for the employees and public, and to build the project quickly," says Michael McCammon, an operations engineer with FDOT. "The theme ‘get in, get out, stay out' is common in transportation projects in Florida, and the Panasoffkee Creek Bridge project in particular embodied this ideal."
Using the design-build process, FDOT minimized lane closures, adhered to an aggressive schedule, and brought the project from concept to completion in approximately 3 years (instead of the traditional 7) at a cost 42 percent less than estimated for traditional design and construction approaches. In addition, the project marked the first time that Florida used a travel lift crane to construct a bridge. The crane used rails, supported on the median edges of the two existing bridges, and ran the entire 1,367 meters (4,484 feet) of the structures, facilitating safer delivery of materials and equipment without lane closures.
The construction contractor also devised an innovative method to access the work zone in the median. By purchasing the property adjacent to the interstate, the company enabled workers to park nearby and access the median by walking on the existing embankment under the northbound bridge, and then using a temporary aluminum bridge to access the median at the end bent. "This innovation," says McCammon, "contributed to the project's outstanding safety record."
Georgia Turns to Full Road Closures to Reconstruct I-285 Segment
Reconstruction of I-285 between I-675 and I-20 in Atlanta required a 25.4-centimeter (10-inch) mill and inlay, all the way to the old PCC pavement. The unusually deep mill was prompted by a stripped layer of asphalt that had been placed over the old PCC pavement in the late 1970s. The inlay consisted of approximately 17.8 centimeters (7 inches) of Superpave,™ 3.8 centimeters (1.5 inches) of stone matrix asphalt, and 3.2 centimeters (1.25 inches) of coarse, open-graded friction course.
Despite traffic volumes of 120,000 vehicles per day, GDOT and FHWA determined that the most effective way to complete the job would be to shut down I-285, one direction at a time, on weekends only. GDOT estimated that reconstructing the 103 kilometers (64 lane miles) of pavement would take 11 weekends in each direction. The project would have taken more than 2 years using conventional nighttime construction methods. "By closing I-285 in the direction of the work and detouring traffic," says James McGee, a Georgia DOT construction engineer, "we were able to accomplish the work in a much shorter amount of time, which caused less overall impact on the traveling public."
The project involved massive preparations, including media campaigns, mass mailings, community meetings, and dynamic signing to get the word out to the public. GDOT orchestrated detours onto I-75 and I-20 to bypass I-285. During reconstruction, GDOT added to the project scope by reconstructing shoulders, upgrading guardrails, and installing a conduit for an advanced transportation management system. Using four pavers and eight milling machines, contractors paved an average of 12.9 kilometers (8 lane miles) of the deep mill and inlay each weekend. The entire project, including paving and roadside work, was completed in only 12 weekends-6 for each direction.
With the road closed to the public, trucks delivering construction materials to the site did not have to wait in traffic, which ensured a constant supply of fresh material. "As a result," says Walter Boyd, a transportation engineer with FHWA's Georgia Division, "pavement smoothness and quality were excellent because the paving machines ran for hours at a time without stopping."
Hawaii Widens H-1 Through Honolulu
In Honolulu, the Hawaii DOT is adding one lane to H-1 in the westbound direction to alleviate a significant traffic bottleneck during the afternoon rush hour. Known locally as the Waimalu Widening Project, the work will involve adding a long viaduct structure-essentially an elevated overpass-that will cross over several streets and connect the community of Waimalu to other communities in the area.
The need to minimize traffic disruption is a major concern, so the new lane will be constructed under normal traffic conditions. To complete road and bridge construction quickly and efficiently, the project incorporates A+B bidding, quick-change movable barriers, and traffic monitoring and control using ITS technologies. The department expects the project to begin in the spring of 2004 and reach completion in the fall of 2005.
Indiana Hyperfix Project Fixes City Streets to Facilitate Full Interstate Closure
To rehabilitate I-70 and I-65 in downtown Indianapolis in the shortest time possible, the Indiana DOT used incentives and complete closures to traffic, thereby enabling the contractor to work full time at the site.
"Full road closure facilitated completing the project in a much shorter time frame-3 months versus 2 years," says INDOT Commissioner J. Bryan Nicol. "It also resulted in better quality control, a superior product, and a higher degree of safety for the public and project staff."
A significant issue for the Hyperfix project was the potential impact on the public in terms of congestion. Closing an interstate facility for 3 months could cause significant disruptions if not planned and coordinated well. The city of Indianapolis and INDOT managed the closure from the perspective of the metropolitan region, coordinating other projects and restricting construction on I-465, the major detour route. In addition, the city completed strategic improvements to its local street system to prepare for increased traffic on alternative routes. Dubbed "Cityfix," the program resulted in $2 million in intersection and street improvements, including turn and parking restrictions, a moratorium on street cuts by utilities, improved intersections, and added travel lanes at strategic locations.
Another important strategy to reduce the impact of congestion and respond to public concerns was the establishment of a park-and-ride program in the northeastern portion of the metropolitan area, the section anticipated to be affected the most. FHWA provided $1 million in funds from the Congestion Mitigation and Air Quality (CMAQ) Improvement Program to provide express coach service at three locations.
"Work zones are a dangerous environment for both workers and motorists," says Dan Rogers, an INDOT construction engineer. "The mainline closure of I-65 and I-70 not only allowed for higher quality and accelerated construction, but also it created a much safer environment for the project crew and the motoring public."
The $25 million Hyperfix project was completed on July 20, 2003, in 55 days, "exceeding everyone's expectations," according to Commissioner Nicol. "This was a significant accomplishment, 30 days under the schedule, and with the contractor reaping the maximum number of incentives."
Iowa Employs Innovative Sawing in PCC Project
While completing a widening and resurfacing project on Iowa 13 between Manchester and Iowa 3, the Iowa DOT applied a thin PCC overlay to the existing pavement and used a full-depth PCC pavement monolithic widening unit on each side as part of its strategy to ensure a long-life overlay. Innovative aspects of the project included using a longitudinal joint-forming knife, or "bobsled," rather than conventional sawing to initiate the multiple joints in the pavement. Attached directly to the paver, the bobsled creates a weakened plane by moving coarse aggregate out of the path. The result is a barely visible crack that requires no sawing or sealing.
Workers placed 1.6 kilometers (1 mile) of pavement per day, and each segment reached opening strength by the following day. Employing the proper mix-design and maturity methods, Iowa DOT could open the new pavement to automobiles 18 hours after placement and to trucks after 30 hours. The department enhanced safety and capacity by providing a wider road with paved shoulders, while minimizing inconvenience to the public during construction.
"The bobsled has the potential to not only reduce the environmental concerns associated with concrete pavement sawing, but it also may produce a better product at a lower cost," says Division Administrator Phil Barnes with the FHWA Iowa Division.
"This approach to rehabilitation, using the remains of the previous investment to the benefit of the new investment, offers significant promise to local and State officials," adds Gordon L. Smith, P.E., president of the Iowa Concrete Paving Association.
Louisiana Opens Center To Manage Traffic and Emergencies
Dedicated in January 2002, the Advanced Traffic Management/Emergency Operations Center (ATM/EOC) in Baton Rouge is a state-of-the-art facility that integrates traffic surveillance, incident detection, traffic control, motorist information, and emergency response into one management center. New ITS functions recently implemented at the center include advanced traffic signal systems, fiber-optic communications systems, and cameras and other automated equipment to monitor and count traffic, detect speed, and classify lanes. A new project on reduced visibility also is underway, involving variable message signs (VMS), variable speed signs, weather stations, and fog detectors.
The center houses the Baton Rouge emergency medical services, 911 call center, fire and police dispatch, regional traffic engineering, and the offices of homeland security and emergency preparedness. "What makes the ATM/EOC truly unique and important to transportation is the existing and planned integration of traffic, 911 dispatch, and incident management systems," says Division Administrator Tony Sussmann with the FHWA Louisiana Division. "The different government agencies are not just sharing the same control room, they're sharing information."
Maine Upgrades Bridge Over Penobscot River
The Maine DOT is building a new cable-stayed bridge spanning the Penobscot River between Waldo and Hancock counties. In July 2003, the department discovered that deterioration of the existing main suspension cables had reduced the structural integrity of the bridge. A series of measures were implemented as short-term fixes until a replacement bridge is open to traffic.
The Waldo-Hancock Bridge, also known as the Penobscot River Crossing, will be a 646-meter (2,120-foot) single-plane, cable-stayed bridge with a segmental concrete trapezoidal box superstructure and a mainspan of 354 meters (1,161 feet). During planning, the Maine DOT considered how the towers might be used to enhance the bridge. As a result, the latest design proposal includes an elevator leading to an observatory atop one of the bridge's pylons. Windows facing all directions would provide views from 122 meters (400 feet) above the ground. The estimated cost of the project is about $70 million, and the projected opening date is June 30, 2005.
The project uses innovative contracting procedures for design and construction, and a streamlined environmental review process brought the project to construction 6 months after the decision was made to pursue a new river crossing. "It is our hope that this bridge will serve to boost the region's economy by becoming an attraction in and of itself," says Maine DOT Commissioner David Cole.
Minnesota Reconstructs Freeway Using Innovations
The primary innovation that the Minnesota DOT (Mn/DOT) is using for a project to reconstruct the four-lane Highway 52 (ROC 52) in Rochester, MN, is the design-build method of contracting.
The purpose of the project is to replace deficient pavement and bridges, thereby improving safety and the level of service. The project involves completely reconstructing and widening 17.7 kilometers (11 miles) of highway to three lanes in each direction though the western portion of Rochester, MN. The reconstruction includes 7 interchanges, 24 bridges, and installation of ITS technologies.
In addition to using the best-value method to select a contractor, the State employed a number of other innovative practices, including an integrated project management team, a comprehensive quality control/quality assurance (QC/QA) program with substantial incentives for quality performance, a built-in dispute resolution process, and concurrent design and right-of-way acquisition.
Mn/DOT expects schedule and cost benefits to include a shortened construction time (from 11 years down to 4) and at least $30 million savings in inflationary costs alone. Substantial benefits also will be realized from reduced out-of-pocket user costs, less user inconvenience (delay), and substantially lower human and monetary costs associated with crashes. Mn/DOT expects the mainline and crossroad construction on ROC 52 to be finished by the end of 2005.
Mississippi Uses Pavement Warranty on I-55
On I-55 in Carroll County, the Mississippi DOT milled an 11.4-kilometer (7.1-mile) section of hot-mix asphalt pavement and placed a concrete overlay on the four-lane divided facility. The I-55 project relied on A+B bidding to speed up construction time and was completed in 503 days, saving approximately 1 year of construction time compared to the conventional bidding process.
The project also represents the first use of a concrete pavement warranty in Mississippi. The 10-year maintenance warranty required the contractor to provide the PCC mix design, selection of materials, and construction methods.
"In the end," says Roger McWilliams, transportation engineer with the FHWA Mississippi Division, "the contractor successfully completed a project of high construction quality with an excellent ride, while saving approximately 1 year of construction time."
The American Concrete Pavement Association selected the project as a finalist in the 2003 Excellence in Concrete Pavement Awards.
Missouri Replaces Bridge on I-70
The voided slab bridge over I-70 between Lake St. Louis Boulevard and Route 40/61 in St. Charles County, MO, was more than 40 years old, and traffic studies indicated the need for additional lanes to accommodate increased traffic. Through a value-engineering proposal, Missouri DOT's contractor suggested building a new, wider structure rather than widening the existing Lake St. Louis Bridge.
The contractor estimated that a new bridge could be built rapidly using precast deck beam sections and mechanically stabilized earth wall abutments, which would provide a two-span bridge instead of the existing four-span. Lane capacity would increase from two to six lanes, providing two through lanes and one turning lane in each direction. The cost would be an additional $500,000, but the new bridge would offer a safer clearance of 5 meters (16.5 feet) for interstate traffic, in lieu of the 4.9-meter (16-foot) clearance originally designed. In addition, the new deck beam structure would not restrict overheight loads. Finally, building the new bridge reduced the actual construction time and impact on motorists by several months.
The bridge closed on August 3, 2003, and reopened by November 24. The combination of the type of bridge (prestressed box beam) and closing the overpass during construction enabled the contractor to demolish the old bridge and erect the new one in less than 4 months. "To decrease the construction time, local officials agreed to allow the department to close the old bridge, demolish it, and build the new one," says Barry Bergman, project manager with the Missouri DOT.
By reducing the number of spans, the department improved the overall geometrics and increased the efficiency and safety of the interchange. The two-span bridge also allows for widening Interstate 70 to address capacity needs in the future. Maintenance costs decreased as well, since the new bridge was approximately 30.5 meters (100 feet) less than the original facility. An additional benefit of the new structure is that the bridge provides simple architectural enhancement opportunities (such as texturing and staining) for the city of Lake St. Louis.
Montana Issues Bonds to Upgrade U.S. 93
The segment of U.S. 93 between Evaro and Polson, MT, currently is a 90-kilometer (56-mile), two-lane rural highway that is heavily congested and exceeds the statewide average for crash rates. The Montana DOT is developing a series of projects to reconstruct this segment to address operational and safety deficiencies, at an estimated cost of $120 million. The conventional funding scenario would complete the project over a period of 15 to 20 years. The department, however, is proposing to issue bonds so that the work can begin sooner, thus accelerating completion to within 7 years.
"This funding mechanism will enable the traveling public to realize the operational and safety benefits as expeditiously as possible," says FHWA Montana Division Administrator Janice Brown.
New Hampshire to Replace Bridge Quickly
Working with the University of New Hampshire, the New Hampshire DOT plans to replace two existing bridge spans over the Lamprey River on Mill Street in Epping, NH, with a single, butted box beam superstructure supported on rapid-installation, precast structural elements. The existing bridges are deteriorated severely and are on the State's list of bridges and municipal structures that are deemed in the worst condition.
Using precast, high-performance elements and innovative contracting techniques, the department expects the new bridge will be constructed and open to traffic in just 2 weeks. With additional roadway work, the entire project should be completed in 3 to 4 weeks. New Hampshire DOT anticipates that the work will be finished in late summer 2004.
New Jersey Goes Precast for Victory Bridge
The new Victory Bridge, which carries Route 35 over the Raritan River, connecting Perth Amboy and Sayreville, NJ, was designed with a record-setting 134-meter (440-foot) main span-the longest precast cantilever segmental construction in the United States. The long-awaited project will relieve congestion in the region, replacing the aging swing bridge with its no shoulders and four narrow travel lanes. The new fixed structure will be high enough to accommodate marine traffic.
To reduce the construction time, New Jersey DOT (NJDOT) selected the segmental precast construction method for both the superstructure and substructure. The department estimates that by using this type of approach, it can reduce the duration of construction by at least 1 year. By employing segmental precast elements, NJDOT anticipates saving millions of dollars, based on life cycle cost analyses. The new bridge will carry two 3.7-meter (12-foot) travel lanes in each direction with shoulders on each side and a sidewalk. Construction work began in February 2003 and should be complete by February 2006.
New Mexico Employs Creative Alternatives to Cash Incentives
Reconstruction of the I-25 and I-40 interchange in Albuquerque, NM, would require construction or rehabilitation of 55 bridges and 177 kilometers (110 lane miles) of roadway. Lacking viable alternate routes, the New Mexico DOT (NMDOT) had to complete the project while traffic continued to use the roadway.
The original interchange was designed in 1967 to support 40,000 vehicles per day. At the time of its reconstruction, however, the facility was severely overutilized with an estimated 300,000 vehicles using the interchange. Congestion resulted in an average of 1.7 crashes per day with a negative economic impact estimated at about $12 million annually. The project enhanced the level of service and reduced the accident rate on the most heavily traveled interchange in the State. NMDOT estimates that the new interchange will benefit the Albuquerque economy by approximately $1 billion over its first 10 years. The public benefited from reduced travel time, enhanced safety, and environmental improvements.
To minimize disruption to the community, the agency decided to reconstruct the interchange under a single contract with incentives to keep the construction time under 2 years. With little money available for cash incentives, NMDOT offered the contractor innovative incentives, such as access to excess right-of-way if the project was finished ahead of schedule. NMDOT purchased an 8.5-hectare (21-acre) parcel that included about 1.6 hectares (4 acres) of required right-of-way, with the remainder used as a staging area during construction. Since construction was substantially complete before the contract calendar date, the contractor received the deed to the remaining 6.9-hectare (17-acre) parcel. Ultimately, several tracts of land owned by NMDOT and determined to be excess to future highway needs were transferred to the contractor in lieu of cash incentives.
To minimize the impact on traffic, the project team used progressive techniques, such as segmental bridge construction, and established a traffic surveillance system and incident response program for the construction area.
Through close contact with the media during the project, the department cultivated public support by keeping motorists aware of potential delays. In the end, the incentives and careful management paid off: The completed interchange opened to traffic in May 2002, after only 23 months of construction.
New York Uses Precast Decks on Gowanus Expressway
In 2001, the New York State DOT (NYSDOT) replaced approximately 20 bridge spans on the Gowanus Expressway in New York City. After large-scale patching work failed to reduce deterioration of the existing decks in this section of the expressway (I-278) viaduct, NYSDOT determined that full deck replacement with precast panels offered an economical solution.
During weekend closures, the agency installed 3,716 square meters (40,000 square feet) of precast deck panels. The innovative panels consisted of a fabricated steel grid (the bottom portion) and a reinforced concrete slab (the upper portion). The top portion of the main bearing bars of the steel grid extend upward into the reinforced concrete component and act as shear connectors, assuring internal composite behavior. Advantages of this design include light weight, rapid construction, and efficiency of overall structural design. The project was completed in February 2002.
North Carolina Speeds Up Highway Delivery Using Design-Build
U.S. 64 between Wendell and Raleigh, NC, is a heavily congested commuter route and primary east-west highway that currently carries between 45,000 and 65,000 vehicles per day. The Knightdale Bypass in Wake County will route traffic around Knightdale, reducing travel time between Wendell and Raleigh by as much as 30 minutes.
"Because of its connection to eastern North Carolina and the daily congestion for commuters along this route, the Knightdale Bypass is a critical project for the region," says State Transportation Secretary Lyndo Tippett. "By using the design-build process, we will be able to deliver this project about 3 years ahead of schedule."
The North Carolina DOT expects to complete the 15.5-kilometer (9.6-mile) project in early- to mid-2005. The total cost is about $131 million.
North Dakota Enhances Construction Using Fabrics
Although engineering fabrics, or geotextiles, are not new to construction, the North Dakota DOT (NDDOT) recently began using them to facilitate faster construction on urban projects with complex work phasing and congested work areas. The fabrics are used in lieu of more time-consuming subgrade preparations, allowing rapid placement of the granular base and leading to quicker pavement installation.
A successful example includes a $20 million urban project near the North Dakota Capitol grounds through a busy retail area of Bismarck. The project was completed in 2 years, with all of the work concentrated in half of the project's length each year. The engineering fabrics consist of polymeric filaments and are manufactured to specified strength and permeability standards. In this application, the fabric serves the combined purpose of reinforcing the material below the pavement and separating the natural earth material from the aggregate base supporting the pavement. Using engineering fabrics in combination with readily compacted aggregates to replace poor soils eliminates drying and reworking saturated soils and time-consuming compaction required when underlying soils are less than ideal for supporting pavement. The technique reduces the time between removing an existing pavement and placing a new pavement, particularly in urban areas where utilities and other obstacles preclude large-scale operations.
The agency also used the fabrics in projects near a traffic-congested section of I-29 in Fargo and at an interchange to a major regional shopping center. NDDOT project personnel are convinced that this acceleration technique is a significant time saver, adding quality to the pavement support system. "The process reduced the construction time for subgrade preparation by about 50 percent," says Adrian Fesser, construction coordinator for the Bismarck District Office of NDDOT.
Ohio Builds Bridges Faster, Smarter, Better
The Ohio DOT cut construction time by more than half on six bridge projects last year by using its strategic initiative: "Build Bridges Faster, Smarter, Better." Ohio has applied many bridge deck overlays in Cleveland and Cincinnati by closing traffic on major interstate routes after the Friday evening rush hour and opening the bridges before the Monday morning rush, thereby minimizing the impact on traffic during the rehabilitations.
"Ohio DOT is dramatically reducing the inconvenience of road closures for thousands of Ohio motorists by using innovative materials and contracting techniques," says Ohio DOT Director Gordon Proctor.
The department uses a variety of techniques to speed up the construction process, such as prefabricated materials, faster concrete curing methods, and contractor incentives and disincentives. The pilot program uses prefabricated concrete bridge members, which include deck slabs, barriers, and approach slabs that are post-tensioned together onsite. Other innovations include stay-in-place metal forms for the decks and single-span steel construction made continuous with concrete closure pours. Many bridge components can be manufactured offsite and "snapped" into place when crews are ready. In addition, steel forms can remain as part of the structure, eliminating the time needed to remove traditional wooden forms.
"If the program proves successful, it could have enormous implications for the reconstruction of our interstate system," Proctor says. "We've rebuilt about one-third of Ohio's interstate over the past decade, but two-thirds remain. If we can find ways to build these bridges faster, we can dramatically reduce delays for millions of motorists."
"Building bridges faster is more expensive," says Deputy Director Jack Marchbanks of Ohio DOT District 6, "however, Ohio motorists save millions of dollars because of the reduction in travel time delays and the associated fuel, vehicle, and productivity costs." The pilot program will last until 2006.
Oregon Invests in Bridge Delivery
In 2003, the Oregon legislature passed House Bill 2041, which provides $1.3 billion primarily for the replacement and repair of bridges on State highways. Through the Oregon Transportation Investment Act III State Bridge Delivery Program, a total of 365 bridges on the State highway system will be replaced or rehabilitated over the next 10 years. Most of the bridges are located on I-5, I-84, and other National Highway System routes. The program presents the opportunity to showcase alternative delivery methods and innovative technologies and materials.
"Accelerated design and construction techniques are crucial to the timely replacement of these deficient bridges," says FHWA Oregon Division Administrator David Cox. "These techniques will allow the Oregon DOT to minimize the negative safety and economic impacts due to out-of-service and restricted service bridges."
South Carolina Constructs New Parkway
To relieve congestion along U.S. 17 in the Myrtle Beach area, SCDOT initiated the Carolina Bays Parkway project to provide nearly 38 kilometers (21 miles) of controlled-access, six-lane divided freeway on a new alignment between U.S. 501 and SC-9. A number of innovative contracting approaches were used to get this roadway built and opened to the public.
The parkway project consisted of laying asphalt pavement, building 25 bridges, and constructing five new interchanges. The project was developed using the design-build concept with right-of-way acquisition services also included in the contract. A best value/fixed budget proposal outlined the minimum project requirements and additional options. SCDOT set the fixed budget at $232 million. Funding was acquired through the South Carolina State Infrastructure Bank, established by the State in 1997 to provide loans and other financial assistance for major projects. Federal-aid participation was established using advanced construction to facilitate future debt servicing. The contractor accomplished the minimum project scope and all additional options within budget and 6 months early. The parkway was opened to traffic in December 2002.
South Dakota Reduces Impact of Bridge Launch at Rail Yard
In the city of Aberdeen, the South Dakota DOT constructed a 97-meter (318-foot) steel truss bridge on an embankment next to a rail yard. The department minimized interruptions to traffic on the 15 train tracks to less than 16 hours while the truss bridge was moved into place. The contractor transported the 745-metric ton (820-ton) structure across the rail yard on rolling platforms, a launching technique that previously had been used on only one other project in the United States. If SDDOT had chosen to build a more conventional two-span structure, the impact on rail service would have lasted several months and involved relocating a significant amount of track.
In addition, rather than using a conventional painting system, SDDOT opted to "metalize" the steel used in the truss. Metalizing is a protective coating for steel with a low life-cycle cost. The department anticipates that the coating will last the life of the structure, which is estimated to be 75 years. Only minor maintenance may be necessary on the clear coating over the metalized steel, once or twice during the life of the structure. This steel protection option will reduce the potential for future maintenance activities that would affect rail and vehicle traffic.
The project began during the summer of 2000 and was opened to traffic in July 2002.
Tennessee Uses High-Performance Concrete for Bridge Construction
The Porter Road Bridge and Hickman Road Bridge, spanning State Route 840 in Dickson County, TN, both feature precast prestressed concrete girders and cast-in-place reinforced concrete deck slabs. The structures are jointless with integral abutments. This construction results in first-cost savings by avoiding expensive expansion joints and long-term maintenance costs. The Porter Road Bridge was completed in May 2000, and the Hickman Road Bridge was completed a few months later, in September 2000.
The Tennessee DOT used high-performance concrete in the pretensioned girders and reinforced deck slab. Coupled with jointless construction, the girders and deck are monolithic with the abutment wall, and the deck slab is continuous over the intermediate bent. The agency expects this combination of materials and structural system to result in dramatic short- and long-term benefits due to the greater strength and durability of high-performance concrete. Components of the bridges were instrumented to record their performance during all stages of construction and service.
Texas Chooses Precast for Bridge Over Lake Belton
The Texas DOT is working on a $20 million construction project to carry State Highway 36 over Lake Belton. The job includes removing the existing structure and constructing dual bridges.
"Using precast bridge caps, rather than cast-in-place, for the substructure, facilitates rapid and efficient construction," says David Hohmann, bridge design engineer at the Texas DOT. "In addition, the quality of the finished concrete products will be improved compared to cast-in-place products, especially considering the logistics of working out in the middle of a lake."
The project is 50 percent complete, with one half of the ultimate configuration already carrying traffic. The remaining half should be finished in summer 2005.
Utah Uses Design-Build Contracts for Traffic Signal Projects
The Utah DOT recently became one of the first State DOTs to use design-build contracting as a procurement method for traffic signal projects.
In February 2003, UDOT issued a request for qualifications to create a pool of design-build teams for these types of projects. The teams selected for the pool are thereby prequalified to submit proposals to design, construct, or modify warranted traffic signal projects throughout the State.
UDOT continuously studies intersections for crash trends and traffic volumes. When a specific intersection reaches the threshold to warrant a signal installation, the department now can select a contractor from the pool to begin work immediately, completing work in a shorter time than with traditional contracting methods.
"This dramatically reduces the time between when a signal is warranted and when it is turned on," UDOT Initiative Contracting Engineer Bob Dyer says. "It can save us up to 8 months over traditional contracting methods."
Dyer also notes an unexpected benefit from using design-build contracting on traffic signals: avoiding utility relocations that otherwise would have taken place if traditional contracting methods had been used. "This is saving taxpayers and utility users' money while helping us get jobs done faster," Dyer says.
UDOT is using a best-value selection process to choose the design-builder on a project-by-project basis. Two signals have been completed already, with four more currently under construction.
Virginia Widens Bridge Over York River
The George P. Coleman Bridge carries Route 17 over the York River in Yorktown, VA. In October 1993, the State of Virginia awarded a $72.7 million contract to widen the existing 1,143-meter (3,750-foot) two-lane bridge to four lanes using the existing substructure. The original bridge was 9.5 meters (31 feet) wide with no shoulders, and the new structure would be 23.6 meters (77 feet) with full shoulders.
The new bridge was built to improve traffic flow across the York River. The original structure, built in 1952, was designed to carry only 15,000 vehicles per day. By 1986, it was carrying 27,000 vehicles per day, and the Virginia DOT projected the number to grow to 43,000 by 2015. VDOT considered 17 solutions, but selected the widening project as the best in terms of cost, environmental impact, and meeting current and future traffic demands.
Construction included replacing six truss spans approximately 774 meters (2,540 feet) long. Innovative technologies employed in the project included state-of-the-art construction methods, truss spans constructed offsite 48 kilometers (30 miles) downriver at the Norfolk International Terminal and floated to the bridge site on barges with specialty support towers, and lightweight concrete used for the deck to minimize the dead load on existing piers.
These features reduced the time to replace the trusses by 36 days, or 60 percent, and resulted in a 27 percent cost savings. The project marked the first time a bridge had been floated in already prepared to carry traffic. The conventional method of floating only the steel trusses, placing the deck and the barriers on the bridge at the site, and using a temporary floating bridge to handle traffic would have cost VDOT an estimated $15.2 million.
The contract documents allowed two 12-day periods to swap out the old truss spans with the new ones. In May 1996, the contractor completed the swap and restored the bridge to full use in 9 days. The department dedicated the structure on August 2, 1996, after the approach spans were reconstructed and the toll facilities were completed.
Washington State Rolls Bridge into Place
In November 2003, the Washington State DOT (WSDOT) completed the NE 8th Street/I-405 Bridge in Bellevue, marking the completion of the $16.4 million project after 18 months of construction-2 months ahead of schedule. The wider bridge over Interstate 405 makes it easier for commuters and visitors to get in and out of downtown Bellevue on the highway.
The project consisted of replacing the old bridge with a structure 10.7 meters (35 feet) longer and 0.9 meter (3 feet) higher to accommodate widening I-405. An innovative design for the new bridge called for half of the structure to be built in a temporary location and rolled into its permanent position. Conventional reconstruction would have taken the bridge out of commission for up to a year or reduced its capacity by half for even longer. Instead, construction caused relatively few disruptions to area drivers, with most closures limited to nights and select weekends. The contractor moved the 1,996-metric ton (2,200-ton) structure into place in about 12 hours.
Benefits include a wider, safer bridge with more lanes of traffic, space for widening I-405 in the future underneath the structure, and new ramps at a location just south of the bridge that improve downtown access for carpools, vanpools, and buses.
Washington State Rehabs Lewis and Clark Bridge
When upgrading the Lewis and Clark Bridge over the Columbia River between Longview, WA, and Rainier, OR, WSDOT committed to a tight construction window to minimize the impact on the traveling public. Rather than closing the bridge entirely, WSDOT shut it down from 9:30 p.m. to 5:30 a.m. nightly for 120 nights.
To replace the deck panels, the contractor used an innovative approach-a large specialized transport device that helped remove the old deck panels and deliver the new ones. Benefits to the public include leaving the bridge open for normal daytime traffic, which is important due to the bridge's close proximity to the Port of Longview. At a cost of approximately $25 million, the redecking project will extend the life of the Lewis and Clark Bridge for 25 years. WSDOT expects to complete the project by late spring 2004.
West Virginia Uses FRP Decks for Bridge
The West Virginia DOT replaced the existing structurally deficient Howell's Mill Bridge in Cabell County with a superstructure using 727 square meters (7,833 square feet) of fiber-reinforced polymer (FRP) deck on weathering steel beams. Carrying County Route 1 over Mud River, the bridge is a two-span structure 74.5 meters (245 feet) long and 9.9 meters (32.5 feet) wide.
Completed in late July 2003, the project demonstrated the use of FRP technology on a larger-scale project on a secondary route with significantly higher average daily traffic-3,400 vehicles per day. The site conditions required serious hydraulic considerations, given that the existing structure's roadway is submerged during flood events. By employing a slight change in grade and using the lightweight FRP deck to reduce dead load and achieve a minimal structure depth, WVDOT now has a structure capable of withstanding a 100-year storm event.
"The FRP decks are installed easily," says John Bargo, assistant bridge engineer at the FHWA West Virginia Division, "resulting in a shorter construction time, thus reducing delay and making the replacement structure available to the public much quicker." With the application of this innovative technology, WVDOT has provided the public with a longer lasting service life for the replacement structure.
Wisconsin Plans Marquette Interchange
The planned Marquette Interchange in downtown Milwaukee will replace deteriorated structures and improve safety and traffic operational characteristics at the junction of I-43, I-94, and I-794. The estimated cost of the project is $810 million.
Design and construction contracts will provide maximum opportunities for small businesses and disadvantaged enterprises. The project also will employ innovative technologies, such as high-performance steel and concrete to ensure a design life of more than 75 years. The project will be constructed in 4 years, between 2004 and 2008, and two lanes of through traffic will be open in the cardinal directions during construction.
A World of Opportunities
This brief review of past, present, and future highway projects demonstrates the viability of employing innovative technologies programmatically, rather than sporadically, across the country, from the icy North to the tropical South, and from downtown urban areas to rural America. Money is not the deciding factor. The key ingredient is the will and determination of the design and construction teams to make the projects responsive to the needs of the public, whether that means completing construction faster or setting up a shuttle bus service to help travelers get around during construction. The tools are out there-now is the time to embrace them.
Kathleen A. Bergeron is a marketing specialist in FHWA's Office of Infrastructure. She has 27 years of experience in all aspects of marketing, including market research, public relations, and advertising. Her experience includes working for major consumer products corporations, a market research company, consulting engineering firms, and State and Federal transportation agencies.
Reprinted from Public Roads, May/June 2004.
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