1、Designation: A798/A798M 07A798/A798M 13Standard Practice forInstalling Factory-Made Corrugated Steel Pipe for Sewersand Other Applications1This standard is issued under the fixed designation A798/A798M; the number immediately following the designation indicates the yearof original adoption or, in th
2、e case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This
3、practice covers procedures, soils, and soil placement for the proper installation of corrugated steel pipe and pipe-archesproduced to Specification A760/A760M or A762/A762M, in either trench or embankment installations. A typical trenchinstallation and a typical embankment (projection) installation
4、are shown in Figs. 1 and 2, respectively. The pipes described in thispractice are manufactured in a factory and furnished to the job in lengths ordinarily from 10 to 30 ft 3 to 9 m, with 20 ft 6 mbeing common, for field joining. This practice applies to structures designed in accordance with Practic
5、e A796/A796M.1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.1.3
6、This specification is applicable to design in inch-pound units as A798 or in SI units as A798M. Inch-pound units and SIunits are not necessarily equivalent. SI units are shown in brackets in the text for clarity, but they are the applicable values whenthe installation is to be performed in accordanc
7、e with A798M.2. Referenced Documents2.1 ASTM Standards:2A760/A760M Specification for Corrugated Steel Pipe, Metallic-Coated for Sewers and DrainsA762/A762M Specification for Corrugated Steel Pipe, Polymer Precoated for Sewers and DrainsA796/A796M Practice for Structural Design of Corrugated Steel Pi
8、pe, Pipe-Arches, and Arches for Storm and Sanitary Sewersand Other Buried ApplicationsA902 Terminology Relating to Metallic Coated Steel ProductsA978/A978M Specification for Composite Ribbed Steel Pipe, Precoated and Polyethylene Lined for Gravity Flow SanitarySewers, Storm Sewers, and Other Special
9、 ApplicationsA1019/A1019M Specification for Closed Rib Steel Pipe with Diameter of 36 in. 900 mm or Less, Polymer Precoated forSewers and Drains (Withdrawn 2012)3A1042/A1042M Specification for Composite Corrugated Steel Pipe for Sewers and DrainsD698 Test Methods for Laboratory Compaction Characteri
10、stics of Soil Using Standard Effort (12 400 ft-lbf/ft3 (600 kN-m/m3)D1556 Test Method for Density and Unit Weight of Soil in Place by Sand-Cone MethodD2167 Test Method for Density and Unit Weight of Soil in Place by the Rubber Balloon MethodD2487 Practice for Classification of Soils for Engineering
11、Purposes (Unified Soil Classification System)D2922 Test Methods for Density of Soil and Soil-Aggregate in Place by Nuclear Methods (Shallow Depth) (Withdrawn 2007)3D2937 Test Method for Density of Soil in Place by the Drive-Cylinder Method3. Terminology3.1 DefinitionsFor definitions of general terms
12、 used in this practice, refer to Terminology A902. For definition of termsspecific to this standard, refer to 3.2.1 This practice is under the jurisdiction of ASTM Committee A05 on Metallic-Coated Iron and Steel Products and is the direct responsibility of Subcommittee A05.17on Corrugated Steel Pipe
13、 Specifications.Current edition approved Sept. 15, 2007May 1, 2013. Published October 2007June 2013. Originally approved in 1982. Last previous edition approved in 20012007 asA798/A798M - 01.A798/A798M - 07. DOI: 10.1520/A0798_A0798M-07.10.1520/A0798_A0798M-13.2 For referencedASTM standards, visit t
14、heASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 The last approved version of this historical standard is referenced on www.astm.org.This document
15、is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appro
16、priate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.2 Definitions of Terms Specific to This Standard:3.2.1 beddi
17、ng, nthe earth or other material on which a pipe is supported.3.2.2 haunch, nthe portion of the pipe cross section between the maximum horizontal dimension and the top of the bedding.3.2.3 invert, nthe lowest point on the pipe cross section; also, the bottom portion of a pipe.3.2.4 pipe, na conduit
18、having full circular shape; also, in a general context, all structure shapes covered by this practice.3.2.5 pipe-arch, nan arch shape with an approximate semicircular crown, small-radius corners, and large-radius invert.4. Significance and Use4.1 Corrugated steel pipe functions structurally as a fle
19、xible ring which is supported by and interacts with the compactedsurrounding soil. The soil constructed around the pipe is thus an integral part of the structural “system.” It is therefore importantto ensure that the soil structure or backfill is made up of acceptable material and well-constructed.
20、Field verification of soil structureacceptability using Test Methods D1556, D2167, D2922, or D2937, as applicable, and comparing the results with Test MethodD698 in accordance with the specifications for each project is the most reliable basis for installation of an acceptable structure.The required
21、 density and method of measurement are not specified by this practice but must be established in the specificationsfor each project.5. Trench Excavation5.1 To obtain anticipated structural performance of corrugated steel pipe it is not necessary to control trench width beyond theminimum required for
22、 proper installation of pipe and backfill. However, the soil on each side beyond the excavated trench mustFIG. 1 Typical Trench InstallationFIG. 2 Typical Embankment (Projection) InstallationA798/A798M 132be able to support anticipated loads. When a construction situation calls for a relatively wide
23、 trench, it may be made as wide asrequired, for its full depth if so desired. However, trench excavation must be in compliance with any local, state, and federal codesand safety regulations.6. Foundation6.1 The supporting soil beneath the pipe must provide a reasonably uniform resistance to the impo
24、sed load, both longitudinallyand laterally. Sharp variations in the foundation must be avoided. When rock is encountered, it must be excavated and replacedwith soil. If the pipe runs along a continuous rock foundation, it is necessary to provide a suitable soil bedding under the pipe. SeeFig. 3.6.2
25、Lateral changes in foundation shall never be such that the pipe is firmly supported while the backfill alongside is not. Whensoft material is encountered and must be removed in order to maintain the pipe on grade during construction, it must be removedfor at least three pipe widths, unless the engin
26、eer has set another limit.6.3 Performance of buried pipe is enhanced by allowing the pipe to settle slightly under load compared to the columns of soilalongside. Thus, for larger pipes it can be beneficial to purposely create a foundation under the pipe itself which will yield underload more than wi
27、ll the foundation under the columns of soil to each side. It can usually be obtained by placing beneath thestructure a suitable-thickness layer of compressible soil, less densely compacted than the soil alongside. This creates “favorable”relative movement between pipe and the soil on each side. It i
28、s of particular importance on pipe-arches.6.4 Pipe-ArchesAll pipe-arch structures shall have excellent soil support at their corners by both the in-situ foundation andthe structural backfill. See Figs. 4 and 5. They do not require the same degree of support under their large-radius inverts.6.5 The e
29、ngineer is encouraged to develop details specific to the site based on the general principles for foundation conditionsgiven in 6.1 through 6.4.7. Bedding7.1 .Material used for bedding beneath the pipe shall meet the requirements of this section. Material in contact with the pipeshall not contain ro
30、ck retained on a 3-in. 75-mm ring, frozen lumps, chunks of highly plastic clay, organic matter, corrosivematerial, or other deleterious material. It is not required to shape the bedding to the pipe geometry. However, for pipe-arches, itis recommended to either shape the bedding to the relatively fla
31、t bottom arc or fine-grade the foundation to a slight v-shape. Thisavoids the problem of trying to backfill the difficult area beneath the invert of pipe-arches. See Fig. 5.8. Pipe Installation8.1 All pipe shall be unloaded and handled with reasonable care. Pipe shall not be rolled or dragged over g
32、ravel or rock andshall be prevented from striking rock or other hard objects during placement on bedding. Pipe with protective coatings shall beNOTE 1d = 12 in./ft 40 mm/m of fill over pipe, with a 24 in. 600 mm maximum.NOTE 2Section BB is applicable to all continuous rock foundations.FIG. 3 Foundat
33、ion Transition Zones and Rock FoundationsA798/A798M 133handled with special care to avoid damage. Paved inverts shall be placed and centered in the invert. Riveted pipe should beinstalled so that outside circumferential joints point upgrade.8.2 Joining Systems:8.2.1 Purpose of Joining SystemsJoining
34、 systems for corrugated steel pipe serve several purposes: to maintain pipe alignmentduring installation; to join the ends of the pipe sections that will subsequently be buried; to create a continuous flow line; to limitthe amount of infiltration of backfill material into the pipe and to limit exfil
35、tration of the flow through the pipe line.8.2.2 Joining System ComponentsThe joining system shall be specified by the project engineer. It shall conform to therequirements of Specification A760/A760M. The pipe fabricator shall provide the components specified for the project or asdesignated by the f
36、abricator in accordance with the Ordering Information section of Specification A760/A760M. Conformance ofthe joining system components with the project requirements shall be verified upon delivery to the project site.8.2.3 Joining System Installation The performance of the pipe line and the joining
37、system will be achieved only when allcomponents of the pipe system are properly installed. As an integral portion of the pipe system, the joining system must beassembled in accordance with the details in the project drawings or the recommendations provided by the pipe fabricator.NOTE 1W = D for roun
38、d pipe, and W = width of flat bottom arc for pipe-arch.FIG. 4 Soft Foundation TreatmentFIG. 5 Bedding and Corner Zone Treatment for Pipe Arch StructuresA798/A798M 1348.2.3.1 GasketsIf gaskets are a required component of the joining system, they shall be placed on the pipe ends, at the requiredlocati
39、on on the pipe, prior to installation of the coupler or bands or prior to stabbing a bell and spigot joint. For joining systemsincorporating O-rings, the O-ring shall be placed on the spigot end of the pipe when the joint is a stab-type joining system, or oneshall be placed on the end of each pipe t
40、hat forms a joining system that incorporates a coupling band. If the joining system includesa single flat gasket, the gasket shall be placed over the end of the pipe previously placed and then extended over the end of theadjacent pipe after it is positioned, such that approximately half the gasket w
41、idth is on each pipe. Instead of a single flat gasket,two smaller gaskets may be used with one gasket placed on each end of the pipes forming the joint. For pipe supplied with a factoryinstalled band or coupler, no field installed gasket will be required on the pipe end with the factory installed de
42、vice. Whenrecommended by the pipe manufacturer, lubricant shall be applied to the designated surfaces. Once installed, the gasket shall beprotected against damage until the joint is completely installed.8.2.3.2 Coupling BandsCoupling bands shall be placed on the end of the last pipe installed. When
43、installing two part bands,the first portion of the band shall be placed to cover the bottom portion of the pipe. When the subsequent pipe is placed theinstallation of the joining system is completed to ensure proper alignment of the pipeline. The width of the opening between pipeends shall be as rec
44、ommended by the pipe fabricator. The band shall be tightened around the pipe ends to the extent necessary toachieve proper performance of the joining system. The band shall be placed over the pipe being joined in a manner that matchesany corrugations or dimples in the band with the corrugations in t
45、he pipe. Follow the pipe fabricators instructions and methodsfor tightening the bands.8.2.3.3 Sleeve Coupler and Bell and Spigot Joining SystemsIf a field installed sleeve coupler is utilized it shall be placed onthe end of the pipe previously placed.With a bell and spigot system, the first pipe is
46、to be oriented so the bell is open in the directionin which construction will proceed. The subsequent pipe is installed by inserting the spigot, or pipe end without the sleeve coupler,to the maximum depth permitted by the joining system. Follow the pipe fabricators instructions for the method of ass
47、embly anduse of insertion force.8.2.4 Joint BackfillThe joining system shall be selected based on the expected site conditions, specifically the type andgradation of backfill material. The structural backfill material used around the pipe shall be in accordance with the projectspecifications. Backfi
48、ll material shall conform to Section 9, and shall be placed in accordance with Section 10. Care shall beexercised during backfill placement not to damage or dislodge the joining system.9. Structural Backfill Material9.1 Structural backfill is that material which surrounds the pipe, extending lateral
49、ly to the walls of the trench, or to the fillmaterial for embankment construction, and extending vertically from the invert to an elevation of 1 ft 300 mm, or 18 the diameteror span, whichever is greater, over the pipe. The necessary width of structural backfill depends on the quality of the trench wallor embankment material, the type of material and compaction equipment used for the structural backfill, and in embankmentconstruction, the type of construction equipment used to compact the embankment fill. The width of structural backfill shall
