Organic “High-Build” Spray-in-Place Liners – An Emerging Class of Rehabilitation Methods

By Erez N. Allouche, PhD, P. Eng. and Eric J. Steward, Trenchless Technology Center, Louisiana Tech University | June 2009 Vol. 64 No. 6

Summary
Organic ‘high-built’ spray-in-place polymers are coming to age as a viable rehabilitation method for gravity driven, and more recently, pressure pipes. A new generation of rapid setting semi-structural polymeric lining products, such as the Copon Hycote 169HB, which is expected to enter the market place over the next few years, offer mechanical properties that allow it to serve and an alternative to polyethylene-based rehabilitation technologies. The combination of robotic-spray and hand-spray equipment allow spray-in-place polymer to be applied to pipes and conduits as small as 4-inch or as large as 120-inch in diameter, as well as a wide range of cross-sectional geometries. In striving for wider acceptance, spray-in-place polymers were required to undergo appropriate qualification and service testing for pressure pipe applications. Long-term performance characteristics need to be further established and consensus-based design procedures need to be developed. Furthermore, procedures for maintenance, installation of new services, and emergency repairs of rehabilitated pipe sections need to be addressed before these technologies can come to fruition. While facing a number of challenges, ‘high-built’ spray-in-place polymers are expected provide decision-makers with a new set of tools for getting their projects done quicker, with less disruption and economically.

Acknowledgement

The authors would like to acknowledge the financial support provided by SprayRoq Inc. of Birmingham, AL, and Innovative Painting and Waterproofing Inc. of Brea, CA. The contribution provided by Dr. Ray Sterling, director of the TTC, and technical support provided by Nathan Pettit, a technician specialist at the TTC, are also acknowledged.

About the authors: Erez N. Allouche, PhD, P. Eng. is the associate director and associate professor of Civil Engineering for the Trenchless Technology Center at Louisiana Tech University (allouche@latech.edu ). Eric J. Steward is a research associate for the TTC at Louisiana Tech (ejs018@latech.edu).