BACKGROUND

State departments of transportation (DOTs) are increasingly using trenchless strategies to rehabilitate and repair aging infrastructure. Performing pipe repairs to existing systems, as compared to pipe replacement, significantly reduces the construction time and maintenance of traffic operations and roadway reconstruction. With reduced construction time and roadway construction, pipe repairs can increase public safety and cost savings to the state DOTs. One of the most common pipe rehabilitation methods is cured in-place pipe (CIPP) liners. CIPP liners are a trenchless technology that provides a method to structurally rehabilitate existing pipes and conduits with minimal impact to the traveling public. The liner consists of a resin-impregnated material that is inserted into the existing damaged host pipe.

Research is needed to substantiate that CIPP liner technology provides the structural characteristics and durability to extend the service life of the asset. 

OBJECTIVE

The objective of this research is to develop a guide for design, installation, and acceptance of CIPP liners for structural rehabilitation of existing pipelines and conduits and test methods for CIPP liner material.  

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

TASKS

PHASE I—Planning

Task 1.  Conduct a critical review of NCHRP Project 18-20, “AASHTO LRFD Design, Installation, and Standard Practice of Testing for Cured In-Place Pipe Liners” (see Special Note A). In addition, the review should include published and unpublished documentation, and research conducted through the NCHRP; the Federal Highway Administration; other national, state, and local agencies; international organizations; and industry groups.

Task 2.  Synthesize the results of Task 1 to identify knowledge gaps related to the research objective. These gaps should be addressed in the final product or the recommended future research, as budget permits.

Task 3.  Based on the work performed in Tasks 1 and 2, prepare a detailed research plan to be executed in Phase II to achieve the project objective. At a minimum, the research plan shall include an approach to:

• Validate, update, and incorporate the results from NCHRP Project 18-20, “AASHTO LRFD Design, Installation, and Standard Practice of Testing for Cured In-Place Pipe Liners.”
• Design and conduct an experimental program. At a minimum, the program should consider (1) structural properties, (2) soil box testing to demonstrate load carrying capacity of CIPP liner per Table ES-2 (culvert rehabilitation tests being proposed), (3) host pipe type and condition, (4) design service life, (5) materials properties of liner and resin, (6) existing standards, (7) sampling and laboratory test methods including accelerated material testing for service life, (8) installation process including preparation and curing methods, (9) testing procedures to develop the standard practice, and (10) installation anomalies and deficiencies that would be identified during post installation inspections. In addition, testing specimens for design verification should (1) replicate in situ condition and (2) consider the scale effect on the accuracy of the results.
• Build on the work completed under NCHRP Project 18-20 by (1) evaluating proposed design equations and suggest revisions, if needed and (2) developing design procedures of CIPP liners based on the load and resistance factor design (LRFD) method.
• Develop a strategy for securing CIPP cooperative commitments from suppliers, vendors, and contractors. Develop a laboratory test method to verify the proposed structural capacity of rehabilitated conduits using CIPP liner technology for the different materials for liner and resin and curing methods.
• Develop an accelerated laboratory test method to predict liner service life for the different materials for liner and resin and curing methods.
• Develop design examples to demonstrate the application of the design for CIPP liner technology. The design examples will be prepared in Phase III. Include supplemental design tool kits, such as spreadsheets.
• Develop criteria for post-installation acceptance.
• Develop draft language for consideration by the American Association of State Highway and Transportation Officials (AASHTO) to incorporate the research results in a future AASHTO guide (herein called the AASHTO Deliverable).

Task 4. Provide an annotated outline of the proposed AASHTO Deliverable including examples to demonstrate the application of the proposed deliverable.

Task 5. Prepare Interim Report No. 1, which documents Tasks 1 through 4 and provides an updated work plan for the remainder of the research. The updated plan must describe the process and rationale for the work proposed for Phases II through IV.

PHASE II—Execution

Task 6. Execute the research plan according to the approved Interim Report No. 1 and update the annotated outline of the AASHTO Deliverable after consideration of the panel’s review comments.

Task 7. Develop a complete sample section of the AASHTO Deliverable to be selected by the NCHRP. This section should be publication-ready with an appropriate level of detail. The format shall meet the current AASHTO formatting guidelines and it shall include commentary.

Task 8. Prepare Interim Report No. 2, which documents Tasks 6 and 7 and provides an updated work plan for the remainder of the research. The updated work plan must describe the process and rationale for the work proposed for Phases III and IV.

PHASE III—Draft AASHTO Deliverable

Task 9. Develop the remaining sections of the AASHTO Deliverable according to the approved Interim Report No. 2.

Task 10. Prepare design examples and the supplementary tool kits according to the approved Interim Report No. 2.

Task 11. Prepare Interim Report No. 3, which documents Task 9 and 10 and provides an updated work plan for the remainder of the research. The updated work plan must describe the process and rationale for the work proposed for Phase IV.

PHASE IV—Final Products

Task 12. Revise the draft AASHTO Deliverable and design examples after consideration of the panel’s review comments.

Task 13. Prepare a stand-alone technical memorandum titled “Implementation of Research Findings and Products”.

Task 14. Submit the final deliverables, including (1) the AASHTO Deliverable, (2) a final report that documents the entire research effort, (3) the design examples and the supplementary tool kits, and (4) the stand-alone technical memorandum, Implementation of Research Findings and Products.

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