ASTM D2321-14e1 pdf free.Standard Practice for Underground Installation of Thermoplastic Pipe for Sewers and Other Gravity-Flow Applications.
ASTM D2321 provides recommendations for the installation of buried thermoplastic pipe used in sewers and other gravity-flow applications. These recommendations are intended to ensure a stable underground environment for thermoplastic pipe under a wide range of service conditions. However, because of the numerous flexible plastic pipe products available and the inherent variability of natural ground conditions, achieving satisfactory performance of any one product may require modification to provisions contained herein to meet specific project requirements.
5. Materials
5.1 Classification-Soil types used or encountered in bury- ing pipes include those classified in Table I and natural manufactured, and processed aggregates. The soil classifica tions are grouped into soil classifications in Table 2 based on the typical soil stiffness when compacted. Class I indicates a soil that generally provides the highest soil stiffness at any given percent compaction, and provides a given soil stiffness with the least compactive effort. Each higher-number soil class provides successively less soil stiffness at a given percent compaction and requires greater compactive effort to provide a given level of soil stiffness.
6. Trench Excavation
6. I General-Procedures for trench excavation that are especially important in flexible thermoplastic pipe installations are given herein.
6.1.1 Excavation-Excavate trenches to ensure that sides will be stable under all working conditions. Slope trench walls or provide supports in conformance with all local and national standards for safety. Open only as much trench as can be safely maintained by available equipment. Backfill all trenches as soon as practicable, but not later than the end of each working day.
6.2 Water Conirol-Do not lay or embed pipe in standing or running water. At all times prevent runoff and surface water from entering the trench.
6.2.1 Ground Water-When groundwater is present in the work area, dewater to maintain stability of in-situ and imported matcrials Maintain water level below pipe bedding and foun dation to provide a stable trench bottom. Use, as appropriate. sump pumps, well points, deep wells, geofabrics, perforated underdrains, or stone blankets of sufficient thickness to remove and control water in the trench. When excavating while depressing ground water, ensure the ground water is below the bottom of cut at all times to prevent washout from behind sheeting or sloughing of exposed trench walls.ASTM D2321-14e1 pdf free download.