BACKGROUND

In recent years, significant progress has been made in the development of traffic speed deflection devices (TSDDs), with over 20 systems in use globally. In the United States, these devices have gained interest among state departments of transportation (DOTs) due to their ability to collect pavement structural condition data at the network level while operating at traffic speed. As a result, many state DOTs have begun collecting this data to explore its use in pavement management and design applications. However, there are no nationally accepted quality assurance (QA) procedures for TSDDs, and the QA procedures used for falling weight deflectometers cannot be directly applied to them.

As more state DOTs rely on TSDD data for pavement management and design, the lack of standardized QA procedures for measuring and interpreting this data can lead to inaccurate decision-making and improper maintenance strategies. There is a need for a practical, standardized approach to QA for TSDD data that can be applied across various use cases.

OBJECTIVE

The objective of the project is to develop device-independent QA procedures for TSDD data, addressing the challenges posed by its dynamic moving load. These procedures shall address the accuracy, precision, repeatability, and reproducibility of TSDD data used in pavement assessments.

Accomplishment of the project objective will require at least the following tasks.

TASKS

PHASE I – Planning

Task 1. Conduct a literature review to identify QA methods, including quality control (QC), data verification, and acceptance procedures relevant to TSDDs. The review should cover the strengths, limitations, and associated requirements of these methods. It shall include any existing databases, published and unpublished documentation, past surveys, and research conducted both domestically and internationally, as well as contacts with public and private organizations.

Task 2. Identify knowledge gaps related to the project objective based on the review performed in Task 1. These gaps should be addressed in the final product or the recommended future research, as the budget permits.

Task 3. Propose the research plan to be executed in Phase II to achieve the project objective. At a minimum, the research plan shall include a framework to accomplish the following:

• Identify QC requirements for TSDD measurements (e.g., equipment calibration, personnel and device certification).
• Enhance existing methods or develop new methods to effectively verify TSDD data and validate those methods.
• Develop procedures for agencies to establish acceptance parameters for various use cases (e.g., project-level vs. network-level applications, different pavement types).
• Develop draft language for the recommended TSDD QA procedures, including QC requirements, data verification methods, and agency acceptance procedures and parameters. The draft language is for consideration by the American Association of State Highway and Transportation Officials (AASHTO) to incorporate the research results into an official AASHTO publication, such as a guideline, manual, specification, or guide (referred to hereafter as the "AASHTO Deliverables").

Task 4. Prepare Interim Report No. 1, which documents the research performed in Tasks 1 through 3 and provides an updated work plan for the remainder of the research, no later than 8 months after the contract is awarded. The updated plan must describe the process and rationale for the work proposed for Phases II and III.

PHASE II – Execution

Task 5. Execute the work plan according to the approved Interim Report No. 1.

Task 6. Prepare a preliminary draft of the AASHTO Deliverables based on the results of this work.

Task 7. Prepare Interim Report No. 2, which documents Tasks 5 and 6 and provides an updated work plan for the remainder of the research, no later than 20 months after the approval of Phase I. The revised plan must describe the process and rationale for the work proposed for Phase III.

PHASE III – Final Deliverables

Task 8. Revise the preliminary draft of the AASHTO Deliverables after consideration of the panel’s review comments.

Task 9. Present the research findings to appropriate technical committees to collect comments for potential revisions to the AASHTO Deliverables. Update the AASHTO Deliverables based on the comments.

Task 10. Prepare a stand-alone technical memorandum titled “Implementation of Research Findings and Products”.

Task 11. Prepare presentation material, in PowerPoint or another format, for use in webinars to facilitate the use and adoption of the AASHTO Deliverables.

Task 12. Submit the final deliverables, including (1) a final report documenting the entire research effort, (2) the AASHTO Deliverables, (3) the Implementation of Research Findings and Products, and (4) the presentation materials.

STATUS: Proposals have been received in response to the RFP. The project panel will meet to select a contractor to perform the work.