State highway agencies across the country are upgrading standards, policies, and processes to satisfy the 2016 AASHTO/FHWA Joint Implementation Agreement for the AASHTO Manual for Assessing Safety Hardware (MASH). Temporary work-zone devices, including portable concrete barriers (PCB), let on projects after December 31, 2019, must have been successfully tested using MASH 2016. Devices used on projects let before this date may continue to be used throughout their normal service lives. Thus, an opportunity exists to review the performance of existing connections between PCB segments and develop high-performance connections. The new connections between portable concrete barrier segments shall meet the MASH safety criteria as well as reduce the deflection, and improve constructability and durability.
The objective of this research is to develop a guideline for connection details between PCB segments. At a minimum, the guideline shall include two parts: (1) performance summary of the existing connection and (2) development of new connection details between PCB segments.
At a minimum, the following requirements shall be considered during the development of the new connection details:
- Dynamic deflection is limited to 24 in;
- The connection shall satisfy the AASHTO MASH Test Level 3 crash testing requirements;
- Segment length is between 10 and 15 feet;
- Segments are free-standing;
- The connection shall accommodate vertical and horizontal roadway geometry;
- Segments are easy to fabricate, transport, install, and remove;
- Segments are single-slope and F-Shape; and
- The connection shall be durable.
Accomplishment of the project objective will require at least the following tasks.
Task descriptions are intended to provide a framework for conducting the research. The NCHRP is seeking the insights of proposers on how best to achieve the research objective. Proposers are expected to describe research plans that can realistically be accomplished within the constraints of available funds and contract time. Proposals must present the proposers' current thinking in sufficient detail to demonstrate their understanding of the issues and the soundness of their approach to meeting the research objective.
Task 1. Conduct a critical review of owner practices and the contractor’s final report for “NCHRP Project 22-36: Synthesis of the Performance of PCB Systems” (see Special Note A).
Task 2. Summarize the performance of existing PCB connections based on results of Tasks 1. Outline the perceived advantages and disadvantages of each PCB connection.
Task 3. Propose a methodology, to be executed in Phase II, to develop the new connection details including performance criteria and testing program.
Task 4. Prepare an annotated outline of a proposed guideline.
Task 5. Prepare Interim Report No. 1 that documents Tasks 1 through 4 and provides an updated work plan for the remainder of the research. This report must be submitted no later than 4 months after contract award. The updated plan must describe the process and rationale for the work proposed for Phases II and III.
Note: Following a 1-month review of Interim Report No. 1 by the NCHRP, the research team will be required to meet in person with the NCHRP project panel to discuss the interim report. Work on Phases II and III of the project will not begin until authorized by the NCHRP. Phase I shall be limited to $30,000.
PHASE II—Connection Developments
Task 6. Execute the proposed methodology according to the approved Interim Report No.1.
Task 7. Finalize the guideline outline with a detailed description of every section and subsection.
Task 8. Prepare Interim Report No. 2 that documents the results of Tasks 6 and 7 and provides an updated work plan for the remainder of the project. This report is due no later than 15 months after approval of Phase I. The updated plan must describe the work proposed for Phase III.
Note: Following a 1-month review of Interim Report No. 2 by the NCHRP, the research team will be required to meet in person with the NCHRP project panel to discuss the interim report, if necessary. Work on Phase III of the project will not begin until authorized by the NCHRP.
PHASE III—Final Products
Task 9. Develop the draft guideline. The draft is due no later than 2 months after approval of Phase II.
Task 10. Prepare final deliverables including: (1) the final guideline for connection details that reflect consideration of the panel’s review comments, (2) a final report that documents the entire research effort, and (3) a stand-alone technical memorandum titled “Implementation of Research Findings and Products.” See Special Note E for additional information.
Note: Following receipt of the draft final report, the remaining 3 months shall be for NCHRP review and comment and for research agency preparation of the revised final report. Phases II and III shall be limited to a total of $320,000.