1、Designation: F 481 97 (Reapproved 2002)An American National StandardStandard Practice forInstallation of Thermoplastic Pipe and Corrugated Pipe inSeptic Tank Leach Fields1This standard is issued under the fixed designation F 481; the number immediately following the designation indicates the year of
2、original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice describes procedures for handling andinstall
3、ing thermoplastic pipe and corrugated pipe in septic tankleach fields, curtain drains, and from the septic tank to the leachfield. Proper installation ensures that the pipe will satisfactorilyconvey and distribute partially treated waste water to aleaching field for additional treatment and disposal
4、 by soilabsorption. The curtain or perimeter drain will function toprotect the soil absorption capacity of the leach field.1.2 To ensure compliance with local regulatory provisions,the local approving authority (local health departments and soforth) should be contacted regarding specific requirement
5、s forleach field design materials and installation.1.3 This practice applies to pipe and fittings made undereach of the following ASTM specifications:1.3.1 For transport from tank to leach field: SpecificationsD 2680, D 2729, D 2751, D 2852, D 3034, F 405, F 758,F 789, F 810, F 891, F 892, and F 949
6、.1.3.2 Perforated, for use in leach field or curtain drain:Specifications D 2729, D 2751, F 405, F 810, F 891, andF 892.1.4 Pipe intended for installation in accordance with thispractice should have a minimum pipe stiffness as specified inthe appropriate product standard referenced in 1.3.1 or 1.3.2
7、.1.5 The values stated in inch-pound units are to be regardedas the standard.1.6 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determ
8、ine the applica-bility of regulatory limitations prior to use. For specificprecautionary statements, see Section 7.2. Referenced Documents2.1 ASTM Standards:D 1600 Terminology for Abbreviated Terms Relating toPlastics2D 2321 Practice for Underground Installation of Thermo-plastic Pipe for Sewers and
9、 Other Gravity-Flow Applica-tions3D 2680 Specification for Acrylonitrile-Butadiene-Styrene(ABS) and Poly(Vinyl Chloride) (PVC) Composite SewerPiping3D 2729 Specification for Poly(Vinyl Chloride) (PVC)Sewer Pipe and Fittings3D 2751 Specification for Acrylonitrile-Butadiene-Styrene(ABS) Sewer Pipe and
10、 Fittings3D 2852 Specification for Styrene-Rubber (SR) Plastic DrainPipe and Fittings3D 3034 Specification for Type PSM Poly(Vinyl Chloride)(PVC) Sewer Pipe and Fittings3F 405 Specification for Corrugated Polyethylene (PE) Pipeand Fittings3F 412 Terminology Relating to Plastic Piping Systems3F 449 P
11、ractice for Subsurface Installation of CorrugatedPolyethylene (PE) Pipe for Agricultural Drainage or WaterTable Control3F 758 Specification for Smooth-Wall Poly(Vinyl Chloride)(PVC) Plastic Underdrain Systems for Highway, Airport,and Similar Drainage3F 789 Specification for Type PS-46 Poly(Vinyl Chl
12、oride)(PVC) Plastic Gravity Flow Sewer Pipe and Fittings3F 810 Specification for Smooth-Wall Polyethylene (PE)Pipe for Use in Drainage and Waste Disposal AbsorptionFields3F 891 Specification for Coextruded Poly(Vinyl Chloride)(PVC) Plastic Pipe With a Cellular Core3F 892 Specification for Polyethyle
13、ne (PE) Corrugated PipeWith a Smooth Interior and Fittings3F 949 Specification for Poly(Vinyl Chloride) (PVC) Corru-gated Sewer Pipe With a Smooth Interior and Fittings31This practice is under the jurisdiction of ASTM Committee F17 on PlasticPiping Systems and is the direct responsibility of Subcomm
14、ittee F17.65 on LandDrainage.Current edition approved May 10, 1997. Published November 1997. Originallypublished as F 481 76. Last previous edition F 481 94.2Annual Book of ASTM Standards, Vol 08.01.3Annual Book of ASTM Standards, Vol 08.04.1Copyright ASTM International, 100 Barr Harbor Drive, PO Bo
15、x C700, West Conshohocken, PA 19428-2959, United States.3. Terminology3.1 Definitions are in accordance with Terminology F 412and abbreviations are in accordance with Terminology D 1600,unless otherwise specified.3.2 Definitions of Terms Specific to This Standard:3.2.1 dual-wall pipepipe with corrug
16、ated exterior andsmooth interior.3.2.2 pipesmooth or corrugated interior wall thermoplas-tic pipe.4. General Requirements4.1 StoragePipe should be stored with support from a flatsurface to prevent the pipe from developing a permanent set.4.2 HandlingCare should be exercised during loading,unloading,
17、 and in transit because pipe may be damaged byabrasion and sharp edges. Because thermoplastics are tempo-rarily softened by high temperatures, care should be takenunder these conditions to avoid damage during handlingoperations.4.3 If contact with chemicals not ordinarily present insanitary sewage i
18、s anticipated, the approval of the regulatoryauthority to install pipe should be obtained.NOTE 1The manufacturer should be contacted for information onchemical resistance.4.4 Coiled pipe is not recommended for use in leach fieldsbecause it is difficult to install at the proper grade andalignment; it
19、 is acceptable with special equipment installation.NOTE 2Corrugated interior pipe should not be used between thedwelling and the waste water treatment unit (septic tank or similar device)because the corrugations may inhibit the flow of solids contained in thewaste.5. InstallationLeach Field5.1 Leach
20、 fields should be constructed to meet the require-ments of the local Department of Health or other governingauthority, which should be contacted for information andrequirements on design, location, installation, materials, and soforth.5.2 Before installation, pipe should be inspected for damagesuch
21、as kinks, crushed portions, splits, and so forth. Anydamaged portions of pipe shall be cut out as a cylinder anddiscarded. Make a visual check of the bore to ensure it is clearof foreign objects that might impede flow.5.3 Gravel SystemsFor proper waste water flow into thesurrounding soils and to pro
22、vide for support of pipe, a uniformlayer of 4 to 6 in. (100 to 150 mm) of graded aggregate shouldbe placed in the trench bottom and leveled true to grade priorto laying the pipe (see Fig. 1). Aggregate should range from34to 214 in. (13 to 54 mm) in size. The aggregate under the pipeshould not be com
23、pacted; for example, by tamping or walking,as this may damage the soil interface.5.4 Fittings recommended by the pipe manufacturer shouldbe used at all joints and for changes of direction except thatpipe may be bent to a radius of not less than 5 times thediameter.5.5 Unless otherwise specified, pip
24、e should be laid true tograde and aligned in the center of the trench, with the top printline or location stripe at the 12 oclock position so that holesare placed down. It should be held in place by alignmentsupports, such as wooden stakes or steel rods.NOTE 3Some authorities require the covering of
25、 the line withuntreated building paper or a geotextile to prevent entry of aggregate,prior to the next step. This is usually required only in areas that require theperforations to be oriented on the top instead of the bottom of the pipe.5.6 For gravel systems, place aggregate around the pipeuntil on
26、ly the top center is still visible. Make a final check ofgrade and alignment. It is particularly important that the sidewalls be given uniform and continuous support to providelateral restraint against deflection during backfilling operations.Care should be taken to prevent damage to the lines. Do n
27、otpermit a dump truck or front-end loader to dump directly overthe pipe. Call for final inspection by local authority if required.5.6.1 Add additional aggregate until the lines are covered toa minimum depth of 2 in. (50 mm) above the pipe (see Fig. 1).Remove alignment supports, level the aggregate,
28、and backfillto grade with soil. An additional 4 to 6-in. (100 to 150-mm)overfill is recommended to compensate for settling.NOTE 4Some authorities require that the top of the aggregate beprotected from migration by a layer of nonbiodegradable, perviousmaterial such as untreated building paper or a ge
29、otextile. Installers shouldnote that the use of the impervious materials, such as plastic film, preventsupward evapotranspiration. The governing authority should be contactedto determine the type of material required.5.7 For the gravel-less leach lines, the plastic protectivecovering used in shippin
30、g must be removed from the pipebefore backfilling. The geotextile covering of the pipe must becontinuous and not damaged. Gravel-less leach lines should bebackfilled with the soil excavated from the trench. Placeembedment material, free of large particles such as rocks,clods, and other extraneous ma
31、terials up to the spring line ofthe pipe. Work sufficient material along the sides of the pipe toprovide adequate side support, without compacting the mate-rial (see Fig. 2).5.7.1 Add selected backfill to a minimum of 6 in. (150 mm)over the top of the pipe. Remaining backfill may consist ofnative so
32、il. An additional 4 to 6 in. (100 to 150 mm) of overfillis recommended to compensate for settling.NOTE 5A record of the installation should be made, including adimensional sketch, name of installer, date of installation, type and brandof pipe installed, and other system details. It is suggested that
33、 the systemowner be provided with a copy of this record.6. InstallationNon-Perforated Pipe6.1 Non-perforated laterals and connector lines are notnormally bedded in an aggregate envelope but are usuallyNOTE 11 in. = 25.4 mm.FIG. 1 Gravel Leach TrenchF 481 97 (2002)2backfilled with the soil excavated
34、from the trench. Therefore,place embedment material, free of large particles such as rocks,clods, and other extraneous materials, up to the spring line ofthe pipe and compact by hand or mechanical tamping. Worksufficient material under the sides of the pipe to provideadequate side support (see Fig.
35、3).6.2 Take care to avoid contact between the pipe andcompaction equipment. The initial backfill and backfill mate-rial should generally be compacted in such a way that thecompaction equipment is not used directly above the pipe untilsufficient backfill has been placed to ensure that such equip-ment
36、 will not have a damaging effect on the pipe. Refer also toPractice D 2321 or F 449 for additional details and definitions.7. InstallationCurtain Drains7.1 Curtain drains are installed to prevent water seepageinto a leach field area. They should be installed in accordancewith Practice D 2321 or F 44
37、9 and at least 1 ft (0.3 m) deeperthan the leach lines and 8 to 10 ft (2.4 to 3 m) from the leachline. The curtain drain should be directed to a free or pumpoutlet.7.2 When perforated, slotted, or slitted pipe is used, gravelor porous backfill should extend as specified or to any seepplane (see Fig.
38、 4).7.3 If edgedrain is used, permeable soil or gravel backfillmay be used (see Fig. 5).8. Special Precautions8.1 Effect of High TemperaturesPipe can reach compara-tively high temperatures when exposed to the sun and thisreduces the pipe stiffness appreciably. Therefore, precautionsmust be taken to
39、prevent the impact of sharp or heavy objects,the sudden imposition of heavy overburden or excessive pullon such pipe. The pipe regains full strength and stiffness as thetemperature decreases to that of the soil; this will normallyrequire about 5 min.8.2 Effect of Low TemperaturesCare in handling and
40、installation should be exercised under low-temperature condi-tions to avoid damage. As temperatures decrease, some typesof pipe tend to become more brittle and less flexible.9. Keywords9.1 curtain drain; gravel-less; installation; leach fieldNOTE 11 in. = 25.4 mm.FIG. 2 Gravel-less Leach TrenchNOTE
41、11 in. = 25.4 mm.FIG. 3 Non-Aggregate InstallationNOTE 11 in. = 25.4 mm.FIG. 4 Curtain Drain With PipeNOTE 11 in. = 25.4 mm.FIG. 5 Curtain Drain With EdgedrainF 481 97 (2002)3ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentio
42、nedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee an
43、d must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting o
44、f theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box
45、 C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).F 481 97 (2002)4
