BACKGROUND: Traffic speed deflection devices (TSDDs) that measure surface deflection at traffic speeds are used by several highway agencies in the United States and other countries to provide data to help with management of the highway network. For example, these data can be used for assessment of pavement structural condition, selection of pavement treatments, and other purposes. In comparison with traditional pavement deflection measurement (e.g., falling weight deflectometers), TSDDs provide a means for acquiring extensive amounts of data in a short period of time that can be effectively used in pavement management and design.
Recognizing that no widely accepted practices for incorporating the measurements obtained by TSDDs into pavement management and design are currently available, research is needed to identify the deflection-based measurements that are required for pavement structural assessment and other applications and develop a guide that presents procedures for incorporating these measurements into pavement management and design practices.
OBJECTIVE: The objective of this research is to develop a guide for incorporating TSDDs measurements into pavement management and design. The procedure contained in the guide shall be consistent with current practices for management and design of asphalt, concrete, and composite pavements.
Accomplishment of the project objective will require at least the following tasks.
TASKS
PHASE I: (1) Collect and review relevant domestic and foreign literature, research findings, and information relative to the procedures for incorporating TSDDs measurements into pavement management and design. This information may be obtained from published and unpublished information, and contacts with public and private organizations. (2) Based on the review performed in Task 1, identify and evaluate available procedures for incorporating TSDDs measurements into pavement management and design and recommend potential procedures for further consideration/investigation in Phase II. Identify the deficiencies of the recommended procedures and means for addressing these deficiencies. (3) Based on the evaluation performed in Task 2, prepare an updated, detailed work plan to be executed in Phase II that includes an approach for (1) developing the improved or new procedures for incorporating TSDDs measurements into pavement management and design that will be included in the guide, and (2) preparing the guide. (4) Prepare an interim report that documents the research performed in Tasks 1 through 3. Following review of the interim report by the NCHRP, the research team will be required to make a presentation to the NCHRP project panel. Work on Phase II of the project will not begin until the interim report is approved and the Phase II work plan is authorized by the NCHRP. The decision on proceeding with Phase II will be based on the contractor’s documented justification of the updated work plan.
PHASE II: (1) Execute the Phase II plan approved in Task 4. Based on the results of this work, recommend procedures for incorporating TSDDs measurements into pavement management and design, and prepare the guide. (6) Illustrate use of the guide and procedures recommended in Task 5 for different scenarios of state department of transportation applications and identify means to facilitate their implementation. Document the work performed in this task and include as an appendix to the guide. (7) Prepare a stand-alone technical memorandum titled “Implementation of Research Findings and Products” to facilitate implementation of the guide. (8) Prepare material, in a PowerPoint or other format, for use in webinars and presentations to facilitate implementation and use of the guide. (9) Prepare a draft final deliverable that documents the entire research effort. The deliverable shall include (1) a research report documenting the work performed in the project and used to develop the recommended procedures and the guide, (2) the recommended guide, (3) the presentation material, and (4) the implementation plan.
STATUS: Proposal review, contractor selection, etc. in progress.
