Volume 7, Issue 5 (May 2010)
Specifying Plastic Pipes for Trenchless Applications
Plastic pipes are widely used in trenchless applications for both rehabilitation and new construction. What makes a pipe suitable for trenchless installation? What material characteristics and pipe properties should a specifying engineer require from pipe in trenchless applications? Engineers often specify for the same project a number of piping products having significantly different properties. This paper assists the engineer in determining which properties and features are actually important and relevant to a trenchless application and thus which need to be addressed during design. Key properties and features include corrosion resistance, joint reliability, rapid crack propagation resistance, flexibility, static and surge pressure capacity, fatigue resistance, impact strength, pull-in strength, stiffness, safety and ease of tapping and transition to other piping materials, ease of repair, abrasion resistance, cold weather performance, and usage history. The relative importance of these factors to a trenchless application with respect to design, installation, and operation is discussed with an emphasis on the development and preparation of trenchless engineering specifications. In addition, this paper addresses the role that ASTM standards play in defining and quantifying many of these properties. Without standardization it would be hardly possible for a designer to properly select a piping product.