Standard Practice for Design of High-Density Polyethylene (HDPE) Manholes for Subsurface Applications

Importancia y uso:

4.1 Uses—The requirements of this practice are intended to provide manholes suitable for installation in pipeline or conduit trenches, landfill perimeters, and landfills with limited settlement characteristics. Direct installation in sanitary landfills or other fills subject to large (in excess of 10 %) soil settlements may require special designs outside the scope of this practice.

4.1.1 Manholes are assumed to be subject to gravity flow only.

4.2 Design Assumption—The design methodology in this practice applies only to manholes that are installed in backfill consisting of Class I, Class II, or Class III material as defined in Practice D2321, which has been compacted to a minimum of 90 % standard proctor density. The designs are based on the backfill extending at least 3.5 ft (1 m) from the perimeter of the manhole for the full height of the manhole and extending laterally to undisturbed in situ soil. Manholes are assumed placed on a stable base consisting of at least 12 in. (30.5 cm) of Class I material compacted to at least 95 % standard proctor density or a concrete slab. The foundation soils under the base must provide adequate bearing strength to carry downdrag loads.

4.2.1 Manholes installed in sanitary landfills or other fills experiencing large settlements may require special designs beyond the scope of this practice. The designer should evaluate each specific site to determine the suitability for use of HDPE manholes and the designer should prepare a written specification for installation, which is beyond the scope of this practice.

Subcomité:

F17.26

Volúmen:

08.04

Número ICS:

83.080.20 (Thermoplastic materials)

Palabras clave:

downdrag; earth loads; manholes; PE pipe; polyethylene; profile pipe ;