New Successes & New Solutions # 2004 Milan
This paper is a state-of-the-art review of a rapidly expanding market for the municipal Polyvinyl Chloride (PVC) piping industry in the United States and Canada : Trenchless Technology. The reality of municipal underground piping construction and rehabilitation in North America has evolved into a combination of both open-cut and trenchless processes. Conventional North American PVC pipe is non-restrained bell-and-spigot gasket-jointed, installed via open trenching. For piping materials used in various trenchless construction methods, restrained-joints are a necessity to prevent joint separation or over-insertion of the spigot into the bell, since the pipe is either pulled or pushed through underground bores. Several proprietary PVC products are now widely used in trenchless processes such as horizontal directional drilling (HDD) and Sliplining. PVC products used in HDD include TerraBrute™, Fusible C900/C905™, and CertaLok C900/RJ™. Fusible PVC offers a direct alternative to Polyethylene (PE), the material traditionally used in trenchless construction. It is butt-fused by a process similar to that used for joining PE pipe. For rehabilitation of pressure piping systems, Duraliner™ is the only available PVC-based expand-and-form process, which gives renewed structural integrity to the corroding host pipe. Rehabilitation of large-diameter gravity sewer lines is offered by one of three proprietary joint profile-wall slipliner pipes : A2 Liner Pipe™, Vylon Slipliner 3 Pipe™, and Easy-Liner Pipe™. Technical details on these products, as well as a discussion of various design issues related to HDD and Sliplining are given.