Spray applied pipe liners is a trenchless technology that provides a method to structurally rehabilitate concrete and metal gravity storm water conveyance conduits with minimal impact to the travelling public. The liner consists of a cementitious or resin based material that is applied in an existing host storm water conveyance conduit via a centrifugal remote applicator or by manual application. Sufficient soil support and stabilization of the host conduit is required prior to placement of the spray applied liner. The liner will provide the structural load carrying capacity without the requirement to adhere to the host conduit. No single structural design methodology for a spray applied pipe liner currently exists. Vendors either apply design equations outlined in ASTM F1216, which are for Cured In Place Pipe (CIPP), or they use a variety of design approaches and conservatively select the maximum pipe liner material thickness. The AASHTO Subcommittee on Bridges and Structures, T-13 Culverts and the AASHTO NTPEP Technical Committee on Spray Applied Pipe Liners collectively agree that the technology would be well accepted and utilized; provided the spray applied pipe liner creates a fully structural solution. However, the committees have identified the lack of a nationally accepted structural design standard as a roadblock to implementation. Several DOT’s have implemented structural spray applied pipe liners despite the lack of a national design standard or with the understanding that they will be designed according to CIPP design equations. Other DOT’s are waiting for a national design standard to be developed prior to implementing the technology.

- Recommend a design methodology for both cementitious and resin based spray applied pipe liners for structural rehabilitation of gravity storm water conveyance conduits. - Recommend a laboratory test method to verify the proposed structural design for conduits that have been rehabilitated using the spray applied pipe liner technology. - Recommend an accelerated laboratory methodology to determine the liner material durability. - Recommend laboratory material testing for both cementitious and resin based materials.

- Review multiple vendor suggested structural design methodologies for cementitious and resin based pipe liners. Ensure a minimum number of 4 vendors for cementitious and 4 vendors for resin based materials are solicited for input. - Review the Cured In Place (CIPP) design methodology outlined in ASTM F1216-09, Appendix X.1, equation X1.3. Review the design equations, variables, and assumptions to determine if the methodology is applicable for spray applied liners. - Review completed and active research that pertains to spray applied pipe liners. - Survey US State DOT’s and Canadian Agencies to identify use and inspect a field installation of resin material and cementitious material. - Recommend a structural design methodology for cementitious and resin based spray applied liners that includes: • LRFD Live and Dead Loads • Host Conduit Conditions and Site Parameter assumptions • Pipe Liner Material Properties - Develop an Excel Spreadsheet to calculate the required thickness for a cementitious and resin based spray applied liner pipe. - Recommend a laboratory test method to verify the structural design for conduits that have been rehabilitated using the spray applied pipe liner technology. - Recommend an accelerated laboratory methodology to determine the liner material durability. - Recommend laboratory material testing for both cementitious and resin based materials.

We request $25,000 per state for FY2016, or for FY2017 if their funding isn’t available for FY2016. The AASHTO NTPEP Technical Committee on Spray Applied Pipe Liners will implement findings of the research in a Project Work Plan that will be used to conduct product evaluations for use by State DOTs. A design methodology for spray applied liners may be used by other AASHTO design committees and data collected through the NTPEP program can be used to validate and refine the design methodology as Vendor products are tested.