U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
|Accelerating Infrastructure Innovations|
Publication Number: FHWA-HRT-05-026
Date: May 2005
The first tunnel management system (TMS) designed for nationwide use has received a real world tryout in Washington, DC, providing the District Department of Transportation (DDOT) with a valuable tool for future monitoring of the condition and performance of its highway tunnels.
Released in 2003 and available to highway and transit tunnel owners and operators across the country, the TMS was jointly developed by the Federal Highway Administration (FHWA) and the Federal Transit Administration (FTA). It is comprised of two manuals and an accompanying software program. The Highway and Rail Transit Tunnel Inspection Manual (Publication No. FHWA-IF-05-002) and Highway and Rail Transit Tunnel Maintenance and Rehabilitation Manual (Publication No. FHWA-IF-05-017) provide guidelines for inspecting, maintaining, and rehabilitating highway and rail transit tunnels. The accompanying software can be used by highway and transit tunnel owners to collect and manage data on tunnel components. The goal of the TMS is to provide uniformity and consistency in assessing the physical condition of tunnels across the United States, many of which are more than 50 years old and showing signs of deterioration, and provide a method for effectively managing tunnel assets.
|A view of the Air Rights Tunnel in Washington, DC.|
Under an FHWA pilot project, the TMS was introduced in Washington, DC, in the fall of 2003 to collect data on and help manage 17 highway tunnels. Data was also collected on two abandoned trolley tunnels. The tunnels range in size from 32.6 m (107 ft) to about 1,036 m (3,400 ft) and are located on both city streets and portions of I-395 that run through the city. "We did not have a tunnel management system in place in DC, so we saw this as a good management tool to systematically monitor tunnel conditions and quantify defects that exist, as well as record a history of maintenance work performed," says Mesfin Lakew, Chief of the Asset Management Division of DDOT.
Gannett Fleming, Inc., which originally developed the TMS for FHWA and FTA, was selected to work with DDOT to implement the system in DC. "The TMS software was easily modified to meet the information technology standards of DDOT," says Chet Allen, Senior Vice President of Gannett Fleming. DDOT requested that condition evaluations of the mechanical and electrical elements of the tunnels be included in the TMS, so the TMS was also modified to accommodate this request. DDOT also recently decided to use a maintenance management database, which links to the TMS. Developed by Gannett Fleming and known as Saber, this system provides flexible schedules for maintenance functions, work orders for specific equipment maintenance, and cost tracking capabilities for all maintenance functions.
"We did not have a tunnel management system in place in DC, so we saw this as a good management tool to systematically monitor tunnel conditions."
Drawings of each tunnel were obtained from existing DDOT files and used to develop standard field inspection forms. These were entered into tablet PCs for field use by tunnel inspectors. Each tunnel was divided into 15-m (50-ft) sections for documentation of deficiencies on the ceilings and walls. Tunnels were closed for inspection overnight, from 7:30 p.m. to 4:30 a.m. Traffic control plans were developed for each tunnel to coordinate lane closures, detours, and notification to the public.
Top: The Virginia Avene tunnel over I-66 is inspected for delaminated areas.
Middle: The centrifugal supply fans in the underground ventilation chamber of the 9th Street tunnel.
Bottom: The east portal of the Virginia Avenue tunnel over the E Street Expressway.
Gannett Fleming then conducted an indepth structural inspection of the walls, ceilings, supply and fresh air plenums, and mechanical/electrical rooms of each tunnel. The inspections were performed using both visual and nondestructive methods, such as hammer tapping. All concrete and tile surfaces were inspected for delaminations, spalls, cracks, efflorescence, areas with bulges, and leaks. Architectural ceiling panels present in two of the tunnels were also visually inspected for damage, water stains, and proper fit. The electrical inspection included a visual inspection of such equipment as switchgear, motor control centers, panelboards, tunnel lighting fixtures and control systems, fire detection systems, closed-circuit television cameras, and ventilation fan control equipment. The large-scale mechanical ventilation systems present in four of the tunnels were also inspected, and measurements were taken of the lighting levels throughout the various tunnels.
All deficiencies that were observed during the inspections were mapped and recorded. Each structural element (such as walls and ceilings) for every 15-m (50-ft) section was evaluated based on a condition rating of 0 to 9, with 0 being a structure that is beyond repair and out of service and 9 representing a newly completed structure. These ratings were entered into the database, along with sketches of each panel, photos, videos of the inspection, and calculations of repair needs. Database users will be able to compare the condition ratings to evaluations collected in future inspections. "The condition of any 50-ft panel section can be compared for any two periods, such as, looking ahead, for 2003 and 2028, in order to monitor the panel's condition over time," says Allen.
The data collection and condition assessment of the structural elements of the tunnels were completed in 2004, with some work continuing on testing of the mechanical and electrical elements of the tunnels. For DDOT, the tunnel management system is here to stay. "We are going to continue using the system to record and monitor tunnel conditions," says Lakew. "We were happy to participate in the pilot project, but it didn't just end with the pilot. We have now taken it a step further and used it to establish base conditions for use with an upcoming Performance Based Tunnel Management Maintenance contract."
"We were happy to participate, but it didn't just end with the pilot. We have now taken it a step further and used it to establish base conditions for use with an upcoming Performance Based Tunnel Management contract."
Gannett Fleming has trained DDOT personnel on using the system. "One advantage of the TMS is that the software does not require computer specialists. Staff with basic skills in Microsoft® products can be trained to use it in a few hours," says Allen.
DDOT expects to realize both cost savings and safety benefits from using the TMS. "It will help us to avoid big repair costs," notes Lakew. "Now we can regularly inspect and monitor conditions, record information, and perform the necessary preventive and routine maintenance to avoid major problems and unexpected breakdowns." Regular inspection and maintenance of tunnel assets such as lights and fans will also result in safer conditions inside the tunnels for motorists.
The TMS has also been used by the North Texas Turnpike Authority to collect data on and assess one tunnel in the Dallas area. For States and cities interested in learning more about the TMS and its implementation by DDOT, FHWA will be sponsoring a showcase workshop on September 20, 2005, in Washington, DC.
The TMS manuals and software were recently updated and reissued. To obtain copies or for more information on the TMS or the upcoming showcase workshop, contact Raj Ailaney in FHWA's Office of Asset Management, 202-366-1567 (fax: 202-366-9981; email: firstname.lastname@example.org). For more information on the TMS implementation in Washington, DC, contact Mesfin Lakew at DDOT, 202-671-4682 (email: email@example.com).
|The east portal of the Barney Circle tunnel.|