Overview
Program managers within state departments of transportation (DOTs) and metropolitan planning organizations (MPOs) are charged with distilling a chaotic universe of identified renewal needs into a logically sequenced program of manageable projects over a period of years. In addition, program managers are tasked with sequencing programs of projects in ways that maximize available resources, minimize disruptions to the traveling public and to adjacent land uses, and recognize political priorities. Over the past several years, substantial progress has been made in the areas of performance measurement, maintenance of traffic, mitigation of congestion in work zones, and alternative contracting and construction techniques. All of this progress has been made in studies and planning designed to minimize, manage, and mitigate disruption to traffic and commerce arising from renewal programs. However, in reality, performance measures are applied largely at the project level, and impacts are not analyzed at the program (mesoscopic) level. The products of this SHRP 2 Renewal project include both a software tool that will assist program managers at DOTs and MPOs in sequencing programs of projects and the training materials on applying that tool.
Task 1 of this project identified the universe of published works that may be applicable to the products of this project. During the Task 2 literature analysis, 135 documents from Task 1 were identified as being “highly relevant” to this project and were reviewed to extract critical information. In Tasks 3, 4, and 5, a similar data set was extracted through interviews with DOTs, MPOs, and other key stakeholders. This allowed the research team (the team) to draw comparisons and identify differences between theory and practice. The team observed that the gap between the state of the art (identified in Tasks 1 and 2) and the state of the practice (identified in Tasks 3 and 4) is quite pronounced and varies widely across the country (Figure ES.1).
Available software platforms with capabilities similar to those considered in this project were identified and analyzed. The lessons learned from the team’s review of the various software platforms and packages provided an excellent basis and critical information for the proposed Work Zone Impact and Strategy Estimator (WISE) tool. As a result of software package reviews, the team concluded the following:
1. Microsimulation software packages that are part of software tool suites with multiple simulation models where one can migrate between macroscopic analysis and microscopic analysis (e.g., VISUM-VISSIM, TRANSCAD-TRANSMODELER, and CUBE) perform best for evaluating regional network impacts. TRANSIMS contains many analysis capabilities, but it is not user friendly.
2. Among the nonproprietary software programs, the Oregon software system performs extremely well. Also performing well are DynusT and QuickZone.
3. Establishing a database of strategies and alternatives that includes production rates and costs would enhance the capabilities of an evaluation tool for assessing work zone impacts on the existing traffic.
4. Many of the software work zone packages are designed to evaluate impacts on the basis of the formation of queues, rather than the potential reduction of travel speeds.
5. Nonproprietary software packages are capable of playing an important role in evaluating and determining the impacts of maintenance of traffic strategies.
6. STEAM, LCCA, and QuickZone are the most robust estimation tools, and variants of these software packages are proposed to be used as part of WISE. DynusT’s router capabilities are useful for studying the impact of intelligent transportation systems (ITS) and capacity changes.
7. SSAM is a useful tool for part of the microscopic evaluation and preliminary engineering and design phases of renewal projects, especially through its capability to estimate safety surrogate measures of performance.
8. Several state DOTs have developed their own spreadsheet-based tools. Although these tools use very coarse estimation procedures, they are easy to use and will serve as templates in the development of the WISE process.
9. WISE is extremely user-friendly, provides flexibility, and can accept inputs from pavement management systems (PMSs) and travel demand models (TDMs).
10. Most of the software, including QuickZone and STEAM, estimate the impacts of work zones as a snapshot comparison between the conditions before and after construction. On a gross level, this process estimates road user cost. The proposed WISE tool considers the excessive road user costs resulting from prolonged renewal activity.
The team identified commercially available software tools and evaluated several that were nonproprietary and easily available. The major thrust of this analysis focused on their potential to be utilized as components of the WISE tool envisioned under this project.
WISE is intended to be used to develop and sequence programs of renewal projects in the Planning Module and to assist in the application of the “Work Zone Rule” in the Operations Module. The WISE tool includes both Planning and Operations Modules and may be applied over large networks or upon complex corridors. The WISE software tool utilizes basic network geometry (link, node, and number of lanes) and basic traffic volume information from virtually any platform, once it is converted to a NEXTA format. Detailed instructions for conversion of network and traffic data into NEXTA formats are included in the WISE Users Guide provided as part of this project.
In the Planning Module, static assignment (user supplied or WISE supplied) is coupled with information regarding the planning characteristics of the program, a user-defined library of demand-based and duration-based renewal strategies, and basic project information. Optimal project sequencing is developed based on user and agency costs. Traffic diversion resulting from projects can be computed by WISE or entered manually by the user for each project. Later, in the Operations Module, the DynusT Dynamic Traffic Assignment platform computes a diversion of traffic based on more specific work zone information. The Planning and Operations Modules perform a “handshake” with one another seamlessly, and the user is not required to re-enter network or traffic data, although additional detail may be added any time it becomes available. The Graphical User Interface (GUI) includes a number of validation checks, as well as user support features.
The WISE software, as well as the Users Guide and Instructional Materials, will be further developed and improved in real-life pilot tests in Phase 4 of this project. The team envisions Phase 4 as an opportunity to fully test and improve the stability and rigor of the WISE code, to more completely develop and integrate the Users Guide and the training materials, and to develop business cases for the application of the WISE tool. Although the Users Guide and the Participants Workbook will remain stand-alone documents, the Users Guide is envisioned as a companion to the Participants Workbook, improving the user’s comfort with WISE’s functionality