1、 Standard Practice for Installation of Annular Corrugated Profile Wall Polyethylene Pipe for Agricultural Drainage or Water Table Control TN-37/2006 105 Decker Ct, Suite 825, Irving, TX 75062 www.plasticpipe.org Foreword This report was developed and published with the technical help and financial s
2、upport of the members of the PPI (Plastics Pipe Institute, Inc.). The members have shown their interest in quality products by assisting independent standards-making and user organizations in the development of standards, and also by developing reports on an industry-wide basis to help engineers, co
3、de officials, specifying groups, and users. The purpose of this technical note is to provide general information on resistance of solid wall polyethylene pipe to a sanitary sewage environment. This report has been prepared by PPI as a service of the industry. The information in this report is offere
4、d in good faith and believed to be accurate at the time of its preparation, but is offered without any warranty, expressed or implied, including WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. Any reference to or testing of a particular proprietary product should not be construed
5、 as an endorsement by PPI, which does not endorse the proprietary products or processes of any manufacturer. Industry members in fulfilling their own compliance responsibilities offer the information in this report for consideration. PPI assumes no responsibility for compliance with applicable laws
6、and regulations. PPI intends to revise this report from time to time, in response to comments and suggestions from users of the report. Please send suggestions of improvements to PPI. Information on other publications can be obtained by contacting PPI directly or visiting the web site. The Plastics
7、Pipe Institute www.plasticpipe.org March 2006 3 Standard Practice for Installation of Annular Corrugated Profile Wall Polyethylene Pipe for Agricultural Drainage or Water Table Control SCOPE This practice is recommended for agricultural subsurface drainage or water table control installations using
8、Annular Corrugated Profile Wall Polyethylene Pipe (Double Wall Pipe). It is not recommended for sanitary or storm sewer applications. Procedures are outlined to minimize pipe deflection or structural damage during and after the installation process. These installation procedures are in accordance wi
9、th “flexible conduit” principles. MATERIAL Pipe and Fittings installed under this specification shall comply with the requirements for materials, test methods, dimensions, and marking in accordance with the current issue of AASHTO M252 type S and SP for 4” through 10” diameters, or ASTM F 2306 for 1
10、2” through 60” diameters except there shall be no requirement for the NCLS test for ASTM F2306 pipe and fittings. GENERAL REQUIREMENTS The maximum and minimum burial depth are affected by the following factors: groove support angle of the trench bottom, bedding, blinding backfill, soil density, enve
11、lope density, envelope placement, pipe stiffness, the live load expected, desired water table depth, and width of trench. Minimum Cover: The minimum recommended cover needed to protect the pipe is 2 ft. Granular bedding or special construction techniques may be used to reduce the recommended minimum
12、 cover. Maximum Cover: The maximum burial depth is influenced by such factors as degree of compaction, type of bedding, support from the trench bottom, trench width, size of pipe, pipe stiffness, weight of backfill, and live loads imposed. In general, when pipes are to be installed without the benef
13、it of an Engineered design, the maximum depth of cover should be limited to 6 feet. For installation at depths greater than 6 feet, an Engineer should be retained to review the design and to develop site specific recommendations to ensure a successful installation. Trench Width: Increasing the trenc
14、h width increases the soil load on the pipe. Side clearances of more than 6 in. on each side should only be used with an engineering design and special construction. Trench width must be at least 3 in. wider than the pipe on each side for open trench installation to allow sufficient bedding to suppo
15、rt the pipe. Minimum Pipe Cover 2 feet Maximum Pipe Cover 6 feet Minimum Trench Width Pipe OD plus 6 inches Maximum Trench Width Pipe OD plus 12 inches 4 Trench Design: Bottom Shape: The bottom shall have a semi-circular or trapezoidal groove (see Fig. 1). The groove must conform as closely as possi
16、ble to the outside diameter of the pipe and envelope 180 degrees of the pipe or there will be insufficient support and pipe deflection will be increased. For flat-bottom trench, bedding must be used for support as shown in Fig. 2. * Per PPI Design Manual Chapter 5 Bedding: If the trench is of the Fl
17、at Bottom type then bedding must be provided for adequate support. Bedding in the form of a Class I or II fill must be placed in the bottom of the trench up to the spring line (Fig. 2) of the pipe. (See Fig. 3 for Class I and II descriptions) Blinding: Material used for this process shall be Class I
18、 II, or III fill material (Fig. 3) and shall not contain any hard object larger than 1 inch (38mm) in diameter and must cover the pipe to a depth of 6 inches (150 mm). Blinding is placed as pipe is being laid. Backfilling: Place the backfill material so that displacement or deflection of the pipe w
19、ill not occur. Backfill should be placed so that it does not drop directly on the pipe. Large stones, frozen material, and dry clods shall not be placed directly over the pipe. The trench shall be backfilled directly after blinding operations are completed. Installation: Pipe shall be bedded and bac
20、kfilled in accordance with the installation detail (Figures 1 large void content, contain little or no fines. IB Manufactured, Processed Aggregates; dense-graded, clean. None Angular, crushed stone (or other Class 1A materials) and stone/sand mixtures contains little or no fines. GW Well-graded grav
21、els and gravel-sand mixtures; little or no fines. GP Poorly-graded gravels and gravel-sand mixtures; little or no fines. SW Well-graded sands and gravelly sands; little or no fines. II Coarse-Grained Soils, clean SP Poorly-graded sands and gravelly sands; little or no fines. GM Silty gravels, gravel
22、sand-silt mixtures. GC Clayey gravels, gravel-sand-clay mixtures. SM Silty sands, sand-silt mixtures. III Coarse-Grained Soils With Fines SC Clayey sands, sand-clay mixtures. ML Inorganic silts and very fine sands, rock flour, silty or clayey fine sands, silts with slight plasticity. IVAAInorganic
23、Fine-Grained Soils CL Inorganic clays of low to medium plasticity, gravely clays, sandy clays, silty clays, lean clays. MH Inorganic silts, micaceous or diatomaceous fine sandy or silty soils, elastic silts. IVB Inorganic Fine-Grained Soils CH Inorganic clays of high plasticity, fat clays. V Organic or Highly Organic Soils OL Organic silts and organic silty clays of low plasticity. OH Organic clays of medium to high plasticity, organic silts. PT Peat and other high organic soils. Fig. 3
