Metrication in highway design and operations

This project sets the stage for implementing a cone penetration testing (CPT) practice in the state of Illinois, providing recommendations for using and interpreting CPT soundings in subsurface investigations. This study also contributes to modernizing Illinois Department of Transportation (IDOT) policy to current CPT-related practices adopted in other departments of transportation, which is consistent with recommendations from the Federal Highway Administration. Toward the goals of this project, CPT soundings across the nine districts of the state of Illinois have been conducted, and available CPT data at IDOT have been evaluated. The generated data have been uniformly processed, generating a database of 156 CPTs distributed across the nine districts. The database also includes shear wave velocity profiles at 28 locations and pore pressure dissipation tests at 45 locations. In addition, information (editable and non-editable) provided by IDOT has been carefully examined. The provided information consisted of boreholes with standard penetration test (SPT) data and laboratory tests on collected Shelby tubes. This information has been used to develop SPT-CPT correlations that can be applied in the state of Illinois and to provide examples of interpreting seismic piezocone test (SCPTu) data in the context of laboratory testing. Due to the several independent, fast, and reliable measurements that can be conducted in a CPT sounding and the fact that they can be done cost-effectively, CPT soundings are increasingly being preferred for in situ testing, and their adoption at IDOT is a positive step forward and consistent with the best practices at other U.S. departments of transportation.

The Illinois Department of Transportation (IDOT) has recently undertaken a quality management program to improve the quality of construction, allow more innovation, and reduce IDOTs management of industry construction programs. The Asphalt Concrete (AC) Quality Control/Quality Assurance (QC/QA) program is a significant part of this quality management program. IDOT accredits the success of the AC QC/QA program to gradual implementation and contractor and industry involvement. In 1991, four projects were constructed under a newly developed QC/QA specification. After reviewing and evaluating feedback from the contractors and IDOT personnel, the specification was revised for use on 1992 projects. In 1992, IDOT let 30 QC/QA projects, and in 1993, 65 QC/QA projects. In 1994 and 1995, most AC projects containing over 225 metric tons (250 tons) of hot-mix asphalt (HMA) were designated as QC/QA projects. In conjunction with this effort on AC quality, an aggregate certification program was implemented. The program ensures that aggregate gradation is highly controlled and is acceptable for incorporation into the mixture. Training programs for contractor QC and aggregate certification were also implemented. Analysis of the data indicates an increase in uniformity of the HMA, potentially leading to a 15 percent increase in fatigue life. IDOT is now examining the implications of developing end-result and performance-related specifications (ERS/PRS) for the AC QC/QA program. In the summer of 1996, one QC/QA project was shadowed and evaluated based on newly developed ERS/PRS.

Department of Transportation (DOT) budgets are being stretched to the limits, while the infrastructure needs of the nation continue to grow. To address this issue, a few DOTs have adopted strategies that promote innovation and motivate industry to propose cost or time saving ideas. The advent of the Design Build (D-B) and General-Contractor-as-Construction-Manager (CM/GC) project delivery methods in highway and bridge construction has established the early involvement of the contractor in the design phase of a project. The next step on this evolution may be Alternative Technical Concepts (ATCs). The Federal Highway Administration (FHWA) has defined an ATC as “a request by a proposer to modify a contract requirement, specifically for that proposer’s use in gaining competitive benefit during the bidding or proposal process and must provide a solution that is equal to or better than the owner’s base design requirements in the invitation for bid (for a design-bid-build project) or request for proposal (for a D-B project) document”. ATCs have been reported to improve constructability, enhance innovation, and ultimately save costs. Issues with ATC use includes: time and resource constraints, confidentiality concerns, submittal issues, and difficulties in conducting fair “apples to apples” evaluations. This paper will report the findings of the research team as it goes through the early stages of identifying best practices for the FHWA to bring uniformity to the ATC process.

The objective of this paper is to highlight recommendations made by fifteen experts from industry and State Departments of Transportation (DOT) regarding the design, implementation, operations, and maintenance of fiber optic communication links presently being used in their transportation management systems. This paper also brings forth the problems faced during the deployment of these systems. The procedure followed for this research was to review the specifications and design guidelines for various Federal Highway Administration (FHWA) projects which have implemented, or are in the process of implementing, fiber optic communication links for their traffic management systems. DOT officials and industry design consultants who were directly involved in the implementation of the FHWA projects were then interviewed on issues concerning system design, operations and management, bidding, and other institutional aspects. The result of these interviews is a set of recommendations ranging from increased use of the latest standards to suggestions for more efficient planning of the traffic management center. These problems and recommendations are presented in this paper. This paper thus offers valuable guidelines for the design and implementation of fiber optic communication systems for future IVHS and transportation management applications.

The Gateway Traveler Information System (Gateway) and www.travelmidwest.com web site (formerly www.gcmtravel.com) provide timely, accurate, and useful traffic information to a variety of public and private constituents. Recurring and nonrecurring congestion directly impacts the economy, the environment, and the safety of the transportation network. The services and data provided by the Gateway have become a mission-critical service of the Illinois Department of Transportation (IDOT) and the geographically-connected roadway operators that are members of the Lake Michigan Interstate Gateway Alliance (LMIGA). This paper details the background and history of LMIGA and the Gateway, specifically www.travelmidwest.com. It highlights the goals of the Gateway and identifies four challenges and the associated resolutions that IDOT and the LMIGA partners use to ensure the Gateway is able to maximize the dissemination of quality traveler information to the staffs of operating agencies, the traveling public, and third party data subscribers. This paper also describes the elements that will impact both the system and the regional partnership as technologies advance, traveler information demands increase, and policies evolve.

Accelerated bridge construction (ABC) methods have been increasingly used in recent years to reduce the impact of construction operations on traffic and mobility. ABC methods, however, often require a higher initial cost, more planning, and additional design coordination. Several tools have been developed to assist decision-makers in the selection of conventional staged construction or ABC methods based on bridge characteristics and requirements. Most of these existing tools, however, are qualitative and depend on the subjective opinion of decision-makers/experts. Accordingly, there is a need for additional research to develop quantitative tools for generating reliable cost estimates for conventional and accelerated bridge construction methods. This report presents the findings of a research project funded by the Illinois Department of Transportation (IDOT) to develop a decision support tool (DST) that IDOT can use to estimate and compare the cost of all bridge construction methods, including conventional staged construction and ABC methods. This project has four objectives. The first objective is to develop a qualitative DST that can be used by IDOT planners and decision-makers to identify all feasible bridge construction methods for any bridge project based on its specific characteristics, requirements, and constraints. The second objective is to create a quantitative cost-estimating DST that can be used to accurately estimate construction, road user, maintenance and rehabilitation, and life cycle costs for all feasible construction methods including conventional and ABC methods. The third objective is to develop guidance for the user interface of the developed DST to explain how it can be used to compare and rank all feasible bridge construction methods based on their individual performance in design, construction, road user, and maintenance and rehabilitation costs. The fourth objective is to evaluate the performance and accuracy of the developed quantitative DST for estimating bridge costs.

This report presents detailed histograms of data from the Regulated Substances Library (RSL) developed by the Illinois Department of Transportation (IDOT). RSL data are provided for state and IDOT region, IDOT district, and county spatial subsets to examine the spatial variability and its relationship to thresholds defining natural background concentrations. The RSL is comprised of surficial soil chemistry data obtained from rights-of-way (ROW) subsurface soil sampling conducted for routine preliminary site investigations. A selection of 22 inorganic soil analytes are examined in this report: Al, Sb, As, Ba, Be, Cd, Ca, Cr, Co, Cu, Fe, Pb, Mg, Mn, Hg, Ni, K, Se, Na, Tl, V, and Zn. RSL database summary statistics, mean, median, minimum, maximum, 5th percentile, and 95th percentile, are determined for Illinois counties and for recognized environmental concern, non-recognized environmental concern, and de minimis site contamination classifications.

The multiple stress creep recovery (MSCR) test, per AASHTO M 332, or as a supplement to M 320, has been widely implemented across the United States and in other parts of the world for assessing the rutting resistance of asphalt binder. Meanwhile, the Illinois Department of Transportation (IDOT) has conducted wide-ranging MSCR testing since 2006 but has not yet implemented this test into the binder specification, which utilizes AASHTO M 320 with other PG Plus tests for modified asphalt binder. This report presents a review of the existing literature and an update of specifications in the United States for the rutting resistance of asphalt binder. The report also presents an analysis of existing MSCR data collected by IDOT and a machine learning model with the ability to predict asphalt binder elastic recovery using MSCR. This model demonstrated the potential effectiveness of MSCR to serve as an appropriate surrogate for this test, but further study is needed of Illinois mixture performance compared to MSCR to best understand how this specification can be implemented for local materials and traffic levels.

In 2006, at the request of the Transportation Research Board (TRB), I published a Synthesis titled: "Use of Geophysics in Transportation Projects" (Sirles, 2006). The 2 year effort provided me terrific insights to how varied the U.S. state department of transportation (DOT) perspective ranged as it regarded the value of geophysics. This perspective was specifically directed at the implementation of subsurface imaging prior to highway or bridge construction. Oddly enough, results from the TRB synthesis were a big surprise to me. The TRB publication (shown in Figure 1) followed a decade of personally delivering classroom-style training at Federal Highway Administration (FHWA) functions. A significant finding in the 2006 synthesis, as shown in Figure 1, is that many respondents to the survey desired additional training/education and experience with the application of geophysics.

In 1977, the Federal Aviation Administration design procedure was changed from a stress analysis based on interior loading to an analysis based on jointed-edge loading. Concurrently, the University of Illinois had developed a finite element computer model which could be utilized when validated. Consequently, the city of Chicago instituted a demonstration-validation rigid pavement test program to determine actual stresses and deflections under aircraft loading for jointed-edge design and validation of the finite element model. In addition, nondestructive test devices of the U.S. Army Corps of Engineers, Illinois Department of Transportation and Federal Highway Administration Region 15 were compared with actual loadings and to each other in order to develop correlations for their use in pavement evaluation and design. Correlation was obtained with the finite element model and has been used for pavement design. Additional research with the nondestructive test devices is necessary and ongoing.

A construction schedule review is an essential aspect of schedule management for U.S. state departments of transportation (DOTs) to deliver transportation construction projects on time. Despite their importance, current literature pays limited attention to addressing schedule quality problems for highway construction projects. This research aims to assess schedule quality problems from DOTs’ perspective and suggests recommendations to improve DOTs’ schedule review practices. To achieve this, two questions were formulated: 1) What schedule problems do DOT schedule reviewers perceive as vital to schedule quality? and 2) What schedule problems do DOT schedule reviewers find repeatedly? This research first reviewed relevant literature and identified 44 schedule quality problems noted about highway construction. Based on these 44 problems, a survey was developed to assess the level of impact and the likelihood of occurrence of each problem. The survey was deployed to Texas Department of Transportation practitioners with schedule review experience. The analysis prioritized the problems by the relative impact and frequency, and DOTs can utilize this analysis to improve their schedule review process and practices. This paper contributes to the academic body of knowledge by investigating the schedule quality problems in highway construction and DOT practitioners’ perceptions of the schedule quality problems. Its industry contribution includes providing the methodology for DOTs to assess their schedule quality problems.

In November 1999, the U.S. Department of Transportation Federal Highway Administration (FHWA) awarded a major Intelligent Vehicle Initiative grant to the Minnesota Department of Transportation (Mn/DOT). Minnesota’s project was a 3-year Generation 0 Specialty Vehicle field operational test for technology that gives lateral guidance and collision avoidance warnings to drivers in low-visibility conditions. Along with Mn/DOT and FHWA, other public and private partners participated in the project. Active operational testing was conducted over the winter of 2001–2002. The purposes of the project were to identify the technology’s safety and operational impacts, to guide future decisions on the technology’s installation on specialized vehicles, and to encourage the development and appropriate deployment of such systems on all vehicle platforms. The technologies were tested in four snowplows, a Minnesota State Patrol squad car, and an ambulance on a 50-mi rural highway. A key aspect of the project was optimizing driver interfaces from the perspective of study of the human factors involved. An overview of the project, including technologies, evaluation, and findings, is presented.

This report provides guidelines for the planning, design, and implementation of Bus On Shoulder (BOS) operations along urban freeways and major arterials. Making BOS a reality requires a closely coordinated partnership effort involving transit agencies, state departments of transportation (DOTs), metropolitan planning organizations (MPOs), enforcement agencies, and the Federal Highway Administration (FHWA). The report should be useful as a decision-making guide to assist transit operators, state DOTs, MPOs, and other stakeholders in assessing the feasibility of the BOS concept, developing safe and effective BOS plans, implementing initial BOS operations, and maintaining or expanding ongoing BOS operations. This guide includes seven case studies in the following cities: Minneapolis-St. Paul, Minnesota; Miami-Dade, Florida; San Diego, California; Old Bridge, New Jersey; Ottawa, Ontario, Canada; Columbus, Ohio; and Atlanta, Georgia.

This monograph examines issues related to the valuation of accident cost saving and the estimation of accident rate reductions likely to be associated with highway investments. The two primary purposes of this research were to 1) develop a practical method for estimating the reduction in accident risk if a roadway is improved and 2) shed light on the appropriate value to be assigned to a reduction in accidents. Chapter 1 contains an overview of the study. Chapter 2 considers in detail the question of how to valuate the safety benefits of highway investments. Information on how state departments of transportation (DOTs) currently evaluate safety benefits was obtained by a survey, the results of which are described in Chapter 3. These results show that state DOTs vary in the values they assign to decreases in accident risks. Most still use a value that is less than the value that the Federal Highway Administration (FHWA) requires to be used in evaluating safety benefits of federally funded projects. The other piece of information needed to estimate the safety benefits of a project--how the project affects the rate and type of accidents--can be obtained from data on accidents and road characteristics. Detailed data bases developed by the Iowa DOT are used to analyze the relationships between road characteristics, accident rates, and accident costs; the results are presented in Chapter 4. The predictive models that were developed enable accident rates and costs of an illustrative two-lane road to be compared with those likely if a specific upgrade were made. Also tested are the sensitivity of accident cost saving per million vehicle miles of travel to the dollar values assigned to reductions in fatal, personal injury, and property damage accidents. Chapter 5 summarizes the research findings and offers three recommendations to improve the ability of state DOTs to take accident cost saving into account when evaluating potential highway investments.

This paper proposes a method for the comprehensive assessment on cross-sectional structures of inter-city motorways in terms of CO2 emission. The index employed in this study is the “Extended Life-cycle CO2 (ELC-CO2)” emission from highways. This takes into account of not only the CO2 generated by highway construction and maintenance works, but also the CO2 emission by traffic, which varies by highway cross-sectional design. Such traffic flow characteristics as traffic flow variations and/or speed-flow relationship is also investigated, which has not been considered in the conventional studies on LCA. The CO2 emission by highway construction and maintenance works is estimated using “combined method”, for elevated, mounded, and tunnel sections respectively. Furthermore, various cross-sectional structures by several geographical and land-use conditions are assessed, through the calculation of ELC-CO2 from each alternative.