1、Designation: C1227 10aStandard Specification forPrecast Concrete Septic Tanks1This standard is issued under the fixed designation C1227; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parenth
2、eses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification covers design requirements, manufac-turing practices, and performance requirements for monolithicor sectional precast concrete septic
3、 tanks.1.2 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.3 This standard does not purport to address all of thesafety concerns, if an
4、y, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2A82/A82M Specification for Steel Wire, Plain, for
5、ConcreteReinforcementA185/A185M Specification for Steel Welded Wire Rein-forcement, Plain, for ConcreteA496/A496M Specification for Steel Wire, Deformed, forConcrete ReinforcementA497/A497M Specification for Steel Welded Wire Rein-forcement, Deformed, for ConcreteA615/A615M Specification for Deforme
6、d and PlainCarbon-Steel Bars for Concrete ReinforcementA706/A706M Specification for Low-Alloy Steel Deformedand Plain Bars for Concrete ReinforcementA996/A996M Specification for Rail-Steel and Axle-SteelDeformed Bars for Concrete ReinforcementC33 Specification for Concrete AggregatesC39/C39M Test Me
7、thod for Compressive Strength of Cy-lindrical Concrete SpecimensC94/C94M Specification for Ready-Mixed ConcreteC125 Terminology Relating to Concrete and Concrete Ag-gregatesC150 Specification for Portland CementC231 Test Method for Air Content of Freshly Mixed Con-crete by the Pressure MethodC260 Sp
8、ecification for Air-Entraining Admixtures for Con-creteC330 Specification for Lightweight Aggregates for Struc-tural ConcreteC494/C494M Specification for Chemical Admixtures forConcreteC595 Specification for Blended Hydraulic CementsC618 Specification for Coal Fly Ash and Raw or CalcinedNatural Pozz
9、olan for Use in ConcreteC685/C685M Specification for Concrete Made by Volumet-ric Batching and Continuous MixingC890 Practice for Minimum Structural Design Loading forMonolithic or Sectional Precast Concrete Water andWastewater StructuresC990 Specification for Joints for Concrete Pipe, Manholes,and
10、Precast Box Sections Using Preformed Flexible JointSealantsC1116/C1116M Specification for Fiber-Reinforced Con-creteC1644 Specification for Resilient Connectors Between Re-inforced Concrete On-Site Wastewater Tanks and Pipes2.2 ACI Standard:3ACI 318 Building Code Requirements for Reinforced Con-cret
11、e2.3 NSF/ANSI Standard:4NSF/ANSI 462005 Evaluation of Components and De-vices used in Wastewater Treatment Systems3. Terminology3.1 For definitions of terms relating to concrete, see Termi-nology C125.1This specification is under the jurisdiction ofASTM Committee C27 on PrecastConcrete Products and
12、is the direct responsibility of Subcommittee C27.30 on Waterand Wastewater Containers.Current edition approved June 1, 2010. Published June 2010. Originallyapproved in 1993. Last previous edition approved in 2010 as C1227 10. DOI:10.1520/C1227-10A.2For referenced ASTM standards, visit the ASTM websi
13、te, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American Concrete Institute (ACI), P.O. Box 9094, FarmingtonHills, MI 48333-9094, http:/www.aci-i
14、nt.org.4Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.2 Definitions of Terms Specific to This Standard:
15、3.2.1 access opening, nhole in the top slab used to gainaccess to the inside of the tank for the purpose of cleaning andremoving sludge without a person actually having to enter thetank.3.2.2 air scum volume, nnumber of cubic inches (centi-metres) in the space between the liquid surface and theunder
16、side of the top slab.3.2.3 baffle, ndevice placed in a tank to dissipate energy,direct flow, retain solids, and/or draw liquid off at a specificdepth.3.2.4 baffle, inlet, ntee or wall segment at or near the inletpipe of a tank designed to direct flow below the liquid surface.3.2.5 baffle, outlet, nt
17、ee or wall segment at or near theoutlet pipe of a tank designed to collect flow from the liquideffluent layer.3.2.6 cement, npowdered substance of lime and claymixed with water to make concrete.3.2.7 connector, ndevice that provides a flexible sealbetween a pipe and the precast concrete tank.3.2.8 c
18、orrosion-resistant, adjmaterials that are resistant todeterioration when in contact with the corrosive materialsfound in a septic tank.3.2.9 dead load, nmass of a structure and all permanentloads imposed on the structure (that is, soil).3.2.10 detention time, naverage length of time a unitvolume of
19、liquid or a suspended particle remains in a tank;mathematically, it is the volume of liquid in the tank divided bythe flow rate through the tank.3.2.11 effective volume, nmaximum amount of liquid andsolids that can be contained in a tank under normal operatingconditions.3.2.12 effluent filter device
20、, ndevice, made fromcorrosion-resistant materials, that separates solid material fromtank liquid before the liquid exits the tank.3.2.13 grinder, ndevice for grinding and flushing cookingwastes; also known as a garbage disposal.3.2.14 inspection opening, nhole in the top slab used forthe purpose of
21、observing conditions inside the tank.3.2.15 joint, nphysical separation where two pieces ofprecast concrete are in contact.3.2.16 liquid effluent layer, narea in a tank made up ofliquids and semibuoyant waste particles after the sludge andscum waste have separated and settled.3.2.17 live load, nload
22、s exerted on or above a structurewhen the source of the load is dynamic and transient.3.2.18 non-sealed joint, njoint in which sealant is notused but in which a machined fit will minimize the movementof liquid from one side of a precast concrete wall to theopposite side.3.2.19 owner, nis by definiti
23、on, end user, customer, orpurchaser.3.2.20 rated volume, ndepth from the bottom of a septictank to the invert of the outlet pipe.3.2.21 scum layer, nbuoyant waste floating near thesurface of liquid, consisting of lighter-than-water materials,such as greases and soaps.3.2.22 sealed joint, njoint that
24、 is sealed to prevent liquidpassing from one side of a precast concrete wall to the oppositeside.3.2.23 septic tank system, nanaerobic digestion chamberin which domestic sewage is received and retained, and fromwhich the liquid effluent, which is comparatively free fromsettleable and floating solids
25、, is then discharged.3.2.24 sludge layer, nheavier waste solids that separateand settle at the bottom of a tank.3.2.25 tee, n“T”-shaped pipe fitting made of corrosion-resistant materials used to connect horizontal piping withvertical piping and used to provide access for cleaning piping.4. Ordering
26、Information4.1 The purchaser shall include the following information inbidding documents and on the purchase order, as applicable tothe units being ordered:4.1.1 Reference to this specification and date of issue.4.1.2 Quantity, that is, number of units ordered.4.1.3 Capacity of tank in gallons or li
27、tres.4.1.4 Special cement requirements including moderatesulfate-resisting cement, Specification C150 Type II, or highlysulfate-resisting cement, Specification C150, Type V. If thepurchaser does not stipulate, the manufacturer shall use anycement meeting the requirements of Specification C150 orC595
28、.4.1.5 Acceptance will be based on a review of the calcula-tions or on proof tests.4.1.6 Design requirements such as depth of earth cover, liveload applied at the surface, and ground water level.4.1.7 Testing for water leakage shall not be required at thejob site unless specifically required by the
29、purchaser.4.1.8 Manufacturer is permitted to require testing on siteprior to backfill.5. Materials and Manufacture5.1 CementPortland cement shall conform to the require-ments of Specification C150 or shall be portland blast-furnaceslag cement or portland-pozzolan cement conforming to therequirements
30、 of Specification C595.5.2 AggregatesAggregates shall conform to SpecificationC33 and lightweight aggregates shall conform to SpecificationC330, except that the requirements for grading shall not apply.5.3 WaterWater used in mixing concrete shall be cleanand free of injurious amounts of oils, acids,
31、 alkalies, salts,organic materials, or other substances that will be incompatiblewith concrete or steel.5.4 AdmixturesAdmixtures, when used, shall conform toSpecification C494/C494M or Specification C618 and shall notbe injurious to other products used in the concrete.5.4.1 Air-Entraining Admixtures
32、Air-entraining admix-tures conforming to Specification C260 shall be used whenthere is a risk that the concrete will be exposed to freezing andthawing. Then the concrete mixture shall contain 5.5 6 1.5 %air by volume as determined by Test Method C231.5.5 Steel ReinforcementSteel reinforcement shall
33、con-form to Specification A82/A82M or A496/A496M for wire,SpecificationA185/A185M orA497/A497M for wire fabric, orC1227 10a2Specifications A615/A615M, A706/A706M,orA996/A996Mfor steel reinforcement bars.5.5.1 Locating ReinforcementReinforcement shall beplaced in the forms as required by the design.5
34、.5.2 Holding Reinforcement in Position During PouringPlacementReinforcement shall be securely held in place bytying, clipping, or welding to maintain position during concreteplacing operations. Welding procedures shall conform to theappropriate material specification. Chairs, bolsters, braces, andsp
35、acers in contact with forms shall have a corrosion-resistantsurface.5.6 Concrete MixturesThe aggregates, cement, and watershall be proportioned and mixed to produce a homogeneousconcrete meeting the requirements of this specification, and inaccordance with Specification C94/C94M or SpecificationC685
36、/C685M. The concrete shall have a maximum watercementitious materials ratio of 0.45.5.7 FormsThe forms used in manufacture shall be suffi-ciently rigid and accurate to maintain the dimensions of thestructure within the stated tolerances. All casting surfaces shallbe of smooth nonporous material. For
37、m releasing agents usedshall not be injurious to the concrete.5.8 Concrete PlacementConcrete shall be placed in theforms at a rate to allow the concrete to consolidate in all partsof the form, and around all reinforcement steel and embeddedfixtures without segregation of materials.5.9 CuringThe prec
38、ast concrete sections shall be cured byany method or combination of methods that will develop thespecified compressive strength at 28 days or less.5.10 Concrete QualityThe quality of the concrete shall bein accordance with the chapter on concrete quality in ACI 318,except for frequency of tests, whi
39、ch shall be specified by thepurchaser. Concrete compressive strength tests shall be con-ducted in accordance with Test Method C39/C39M.5.11 FibersPolypropylene or polyolefin fibers are onlypermitted as a secondary reinforcing material, at the manufac-turers option, in precast concrete septic tanks.
40、For the pur-poses of this specification, secondary reinforcing material isonly used to resist temperature and shrinkage effects. OnlyType III conforming to the requirements of SpecificationC1116/C1116M shall be accepted.5.12 SealantsFlexible sealants used in the manufactureand installation of tanks
41、shall conform to Specification C990.Rigid (mortar) sealing of tank sections is not permitted.5.13 Pipe ConnectionsPipe-to-tank connections shall useflexible connectors conforming to the requirements of Speci-fication C1644.6. Structural Design Requirements6.1 Structural design of septic tanks shall
42、be by calculationor by performance.6.1.1 Design by calculation shall be completed using theStrength Design Method (ultimate strength theory) or theAlternate Design Method (working stress theory) outlined inACI 318. The Strength Design Method is outlined in Chapter 9and the Alternate Design Method is
43、 in Appendix A.6.1.2 Design by performance requires the manufacturer todemonstrate that failure will not occur by physically applyingloads to the product. The load applied shall be 1.5 times theanticipated actual loads.6.1.3 Tanks shall be designed so that they will not collapseor rupture when subje
44、cted to anticipated earth and hydrostaticpressures when the tanks are either full or empty.6.1.4 After conditions are established, loads from PracticeC890 shall be used for design. Unless heavier live loads areexpected, the minimum live load at the surface for design shallbe 300 lbf/ft2(14 kPa).6.1.
45、5 The live loads imposed at lifting points shall beconsidered in the design of the structure.6.1.6 Inserts embedded in the concrete shall be designed foran ultimate load that is four times the working load (Factor ofSafety = 4).6.2 Concrete StrengthThe minimum compressivestrength (f8c) for designs s
46、hall be 4000 psi (28 MPa) at 28 daysof age.6.3 Reinforcing Steel PlacementThe concrete cover forreinforcing bars, mats, or fabric shall not be less than 1 in. (25mm).6.4 OpeningsThe structural design shall take into consid-eration the number, placement, and size of all openings.6.5 Lift equipment sh
47、all be designed for an ultimate loadthat is five times the working load (Factor of Safety = 5).7. Physical Design Requirements7.1 CapacitySizes are generally specified by local regu-lations and they shall supersede the following guidelines.When local regulations are not available, the following mini
48、-mum sizes will be required:1-bedroom residence 750 gal (2800 L)2 and 3-bedroom residence 1000 gal (3800 L)4-bedroom residence 1200 gal (4500 L)5-bedroom residence 1400 gal (5300 L)Motels 100 gpd/unit (380 Lpd/unit)Restaurant 70 gpd/seat (265 Lpd/seat)Office building 20 gpd/seat (75 Lpd/seat)Additio
49、nal capacity is required when grinders are available7.2 Shape:7.2.1 There shall be a total of no less than 25 ft2(2.3 m2)ofsurface liquid area and a total inside length of at least 6 ft (2 m)between inlet and outlet of the tank.7.2.2 The air scum volume above the liquid shall be at least1212 % of the volume of liquid but not less than 9 in. (230mm) high for entire surface above liquid.7.2.3 Minimum water depth shall be 36 in. (900 mm) unlessotherwise approved by local code or jurisdiction.7.2.4 Maximum liquid depth shall be 72 in. (1
