Institute for Transportation

About the research

• Develop risk assessment procedures to identify critical bridges in a bridge network
• Develop bridge vulnerability assessment guide
• Develop concepts for mitigation and structural protection of bridges

Soon after the attacks of September 11, 2001, the Federal Highway Administration (FHWA) and the American Association of State Highway and Transportation Officials (AASHTO) assembled a Blue-Ribbon Panel of experts to develop strategies and provide guidance to improve the safety and security of bridge and tunnel infrastructure. This effort led to recognizing that the threat is real and can be devastating, risk assessment is necessary, and engineering guidance are needed based on research. Building on current and past efforts, the goal of this project is develop procedures to assist professionals and bridge owners identify critical bridges and to develop procedures to assess their vulnerability to explosions (terrorist’s bomb attacks). Potential Benefits of the Project The procedures and design guides developed in this project will benefit the bridge owners, designers, inspectors, and professionals nationwide.

Funding Sources:
California Department of Transportation
Midwest Transportation Consortium
University of Missouri – Columbia

About the research

Develop an optimization-based decision support system to address depot and fleet management issues associated with typical DOT maintenance system operations. Sub-objectives include:

• Develop a protocol for determining the desired level of service and the required constraints.
• Develop an integrated model and efficient algorithms for large scale applications.
• Validate the model/algorithms and apply results to the state of Missouri.

Abstract

Most DOTs have multiple maintenance depots or sheds to provide public services such as winter snow removal, roadway striping, mowing, and herbicide application. The location of these sites has typically been based on geographical dispersion to provide the best coverage from a distance perspective. Each depot has a fleet of trucks to cover an assigned service sector. The location of depots as well as the fleet assignment is usually determined by the managers and engineers based on their experience, not on scientific evaluation processes. This research proposes, through systems analysis, to design a decision support system that provides DOT decision makers with efficient management tools for depot location and fleet assignment operations.

Potential Benefits of the Project

The decision support system will be able to evaluate any given scenarios and compute the optimal numbers of depots and trucks. These solutions can then be used directly or used as part of a decision support system for the asset management aspects of this important problem.

Funding Sources:
Midwest Transportation Consortium
Missouri Department of Transportation

About the research

Traffic volume increases and an aging infrastructure create the need for reconstruction, rehabilitation, and maintenance of existing facilities. As more motorists feel that delays should be minimal during highway renewal projects, lane closures that reduce capacity through the work zone should not create unreasonable delays. In order to facilitate the determination of when a lane closure is permitted during the day, some state transportation agencies (STAs) have developed lane closure policies, or strategies, that they use as guidance in determining daily permitted lane closure times. Permitted lane closure times define what times of the day, week, or season a lane closure is allowed on a facility and at a specific location or segment.

This research addresses the lane closure policies of several STAs that were reputed to have good lane closures policies or strategies and that were selected by the project advisory committee for further research. These agencies include the following: –California Department of Transportation (Caltrans) –Colorado Department of Transportation (CDOT), Region 1 and Region 6 –Indiana Department of Transportation (INDOT) –Minnesota Department of Transportation (Mn/DOT), Metropolitan District –Missouri Department of Transportation (MoDOT) –Ohio Department of Transportation (ODOT) –Wisconsin Department of Transportation (WisDOT).

A survey was sent to each STA to help determine its actions with respect to the undocumented mechanics of the policy and to find some common ground for policy comparison.

About the research

Cantilevered signal, sign, and light support structures are used nationwide on major interstates, national highways, local highways, and at local intersections for traffic control purposes. Recently, there have been a number of failures of these structures that can likely be attributed to fatigue. In light of the fact that there is considerable uncertainty in the calculation of vortex shedding loads in both the American Association of State Highway and Transportation (AASHTO) and the Canadian Highway Bridge Design Code (CAN/CSA) code provisions, the current equations used for vortex shedding fatigue design need to be reevaluated and likely re-formulated or modified. A luminary support structure or High Mast Light Pole (HMLP) is generally susceptible to two primary types of wind loading induced by natural wind gusts or buffeting and vortex shedding, both of which excite the structure dynamically and can cause fatigue damage. Vortex shedding is a unique type of wind load that alternatively creates areas of negative pressures on either side of a structure normal to the wind direction. This causes the structure to oscillate transverse to the wind direction. The primary objective of this study was to develop a procedure for predicting wind loads in the time domain for the fatigue design of slender, tapered luminary support structures. To accomplish this, monitoring of long-term response behavior of a HMLP subjected to wind-induced vibration was needed. This was accomplished by full-scale measurement of the response of a HMLP located near Mason City next to I-35 in Iowa. Wind tunnel testing was also conducted to determine the required aerodynamic parameters of the pole cross section. Further, these aerodynamic parameters were cast into a coupled dynamic model for predicting the response of any HMLP in the time domain. Finally, the model was validated by comparing its results with the data collected from field monitoring.

Funding Sources:
Midwest Transportation Consortium

About the research

Innovative contracting methods are being constantly refined to meet the challenges facing state departments of transportation (DOTs) in their efforts to rehabilitate the nation’s infrastructure. These contracting methods emphasize best value practices and attempt to minimize construction cost and service disruptions to the traveling public. The importance of innovative contracting methods stems from the flexibility they offer to state DOTs in the procurement and delivery of construction. One innovative contracting method that appears to be underutilized is flexible start date contracts which allow contractors to schedule their work during dates that optimize schedules and minimize the public impact of their projects. The present paper describes an exploratory investigation of flexible start/fixed duration contracting. The paper presents the current practices of a number of state DOTs along with a case study of the Paseo Bridge rehabilitation project in Kansas City, Missouri. The results of this investigation demonstrated the advantages of flexible start/fixed duration contracting and its potential benefits in large transportation projects in urban settings.

About the research

Mobility and safety through work zones has become a prominent issue in work zone planning because motorists commonly expect minimal disruption to their normal driving habits. However, work zones can create unacceptable delays and queues if not adequately addressed.

State transportation agencies (STAs) are currently working towards meeting the requirements of the Federal Highway Administration?s Work Zone Safety and Mobility Rule, 23 CFR, Part 630. This rule requires STAs to systematically manage the impacts of work zones on federal-aid highways and other projects that have significant impact on road users. STAs therefore use various congestion mitigation strategies in their transportation management plans.

This synthesis identifies and discusses many frequently used strategies and many strategies that are relatively new to several agencies. When developing transportation management plans, a well-rounded and comprehensive group of strategies can be made to work together to mitigate work zone congestion to levels that are acceptable to motorists. This synthesis thus provides a tool for STAs to use in the work zone planning stages of a project.

About the research

After Hurricane Katrina, in the Gulf Coast region, millions of lives were impacted because of the lack of availability of transportation, shelter, food, water, drugs, etc. Hurricane Katrina raised many concerns in terms of the federal government?s capability, including their operational plan and necessary coordination strategies between state and federal governments to come up with a robust response in these catastrophic incidents. It has become apparent that developing a better operational plan is needed. To improve disaster relief, better logistics planning, which also requires better forecasting methods, is needed. Furthermore, to increase collaboration at all levels, it is also necessary to have more reliable communication technologies and a better information technology structure which will enable better coordination between different agencies. Utilizing technologies such as GIS and real-time tracking systems will ensure that the available disaster relief stocks will be distributed fairly to everybody.

Funding Sources:
Midwest Transportation Consortium

About the research

Prefabricated elements have the opportunity to reduce the duration of closed lanes during highway reconstruction. Typically, an element that is prefabricated off-site and installed, rather than being constructed in-place, diminishes the duration of on-site construction activities and, therefore, minimizes the disruption and congestion of traffic due to shorter duration lane closures.

This case study presents an analysis of the benefits and costs of using prefabricated pavement panels. The case study involves a small panel replacement project, conducted by the Minnesota Department of Transportation, involving the installation of precast concrete pavement panels. The installation segment consisted of a 218 ft. continuous stretch of 12 ft. wide pavement. The objective of the test project was to evaluate the use of precast pavement panels to reduce construction time, thus reducing overall and continuous motorist delay due to a lane closure.

The results of the benefit-to-cost analysis conducted as part of this case study suggest that for small projects that consist of only a few panels, using prefabricated panels to reduce work zone user costs is cost-effective; however, as projects involve more prefabricated panels, the construction costs quickly escalate and become cost prohibitive.

About the research

Fuel surcharge policies are utilized by transportation companies to transfer the expense associated with fuel prices to their customers. As fuel surcharges have become a significant portion of the expenses on transportation invoices, an increasing number of shippers are expressing more interest in these policies. The objective of this study is to discover how less-than-truckload (LTL) carriers develop and utilize fuel surcharge policies to recover their fuel expenses. Thirty-nine top LTL carriers were called on to explain their perspectives and methodologies with regard to fuel surcharge policies. Part-to-whole qualitative analysis was conducted to summarize responses from a standardized interview protocol. In addition, 25 published fuel surcharge policies were obtained and analyzed to explore the disparities among LTL fuel surcharge policies. Findings show that, while carriers were reluctant to discuss their fuel surcharge development, in practice there were two primary methodologies that left all carriers with very similar fuel surcharge policies.

Funding Sources:
Midwest Transportation Consortium

About the research

The dramatic rise in fuel prices and growing environmental concerns are pressing freight transportation companies to pursue new systems and methods to improve fuel efficiency and reduce their environmental impact. While select major carriers appear to be leading efforts to adopt technologies that support a dramatic improvement in fuel performance, there appears to be little understanding as to the breadth and depth of efforts being taken by the broader motor carrier community, consisting of over 20,000 companies of all sizes. The purpose of this study was to investigate the level of adoption of technologies and policies to support improved fuel efficiency among motor carrier fleets.

Funding Sources:
Midwest Transportation Consortium