6-1 OVERVIEW OF INSTALLATION CONSIDERATIONS

Installation of Hancor polyethylene pipe is in most respects very much like that of any quality pipe installation. The strength of a pipe system should be considered a combination of the pipe itself and the backfill envelope. Proper construction maximizes the drainage capabilities designed into the pipe by maintaining alignment and load-carrying ability.

Recommendations for proper backfill and installation for Hancor products are based primarily on the requirements of ASTM D2321 “Recommended Practice for Underground Installation of Flexible Thermoplastic Sewer Pipe” with few exceptions.

The elements regarding backfill that are addressed in this section are as follows:

Proper backfill material selection - A variety of materials can be used as structural backfill with the final decision, many times, based on what is most available locally. Native soil may be an appropriate material providing it meets some basic criteria established in this section.

Proper backfill compaction - Compaction forces out air and moisture to provide a more stable structure. Minimum compaction levels are based on the material characteristics and the design load; some situations may require the use of some type of mechanical compactor while others require simply tamping the material to eliminate voids.

Proper backfill structure - An adequate quantity of structural backfill is necessary to ensure adequate support. Undisturbed native soil from a trench wall often provides additional support. Typical trench dimensions and the effect of the trench wall are discussed in this section.

In addition, this section discusses job-site handling, trench construction and pipe installation for Hancor products, compaction methods, and several specialized installation considerations.