1、Designation: C 1227 07cStandard Specification forPrecast Concrete Septic Tanks1This standard is issued under the fixed designation C 1227; 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 paren
2、theses indicates the year of last reapproval. Asuperscript epsilon (e) 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 sep
3、tic tanks.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.3 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 est
4、ablish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2A 82/A 82M Specification for Steel Wire, Plain, for Con-crete ReinforcementA 185/A 185M Specification for Steel Welded Wire Rein-forcemen
5、t, Plain, for ConcreteA 496/A 496M Specification for Steel Wire, Deformed, forConcrete ReinforcementA 497/A 497M Specification for Steel Welded Wire Rein-forcement, Deformed, for ConcreteA 615/A 615M Specification for Deformed and PlainCarbon-Steel Bars for Concrete ReinforcementA 706/A 706M Specifi
6、cation for Low-Alloy Steel De-formed and Plain Bars for Concrete ReinforcementA 996/A 996M Specification for Rail-Steel and Axle-SteelDeformed Bars for Concrete ReinforcementC33 Specification for Concrete AggregatesC 39/C 39M Test Method for Compressive Strength of Cy-lindrical Concrete SpecimensC 9
7、4/C 94M Specification for Ready-Mixed ConcreteC 125 Terminology Relating to Concrete and ConcreteAggregatesC 150 Specification for Portland CementC 231 Test Method for Air Content of Freshly MixedConcrete by the Pressure MethodC 260 Specification for Air-Entraining Admixtures for Con-creteC 330 Spec
8、ification for Lightweight Aggregates for Struc-tural ConcreteC 494/C 494M Specification for Chemical Admixtures forConcreteC 595 Specification for Blended Hydraulic CementsC 618 Specification for Coal Fly Ash and Raw or CalcinedNatural Pozzolan for Use in ConcreteC 685/C 685M Specification for Concr
9、ete Made by Volu-metric Batching and Continuous MixingC 890 Practice for Minimum Structural Design Loading forMonolithic or Sectional Precast Concrete Water andWastewater StructuresC 990 Specification for Joints for Concrete Pipe, Manholes,and Precast Box Sections Using Preformed Flexible JointSeala
10、ntsC 1116 Specification for Fiber-Reinforced Concrete andShotcrete2.2 ACI Standard:3ACI 318 Building Code Requirements for Reinforced Con-crete2.3 NSF/ANSI Standard:4NSF/ANSI 462005 Evaluation of Components and De-vices used in Wastewater Treatment Systems3. Terminology3.1 For definitions of terms r
11、elating to concrete, see Termi-nology C 125.3.2 Definitions of Terms Specific to This Standard: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 volu
12、me, nnumber of cubic inches (centi-metres) in the space between the liquid surface and theunderside of the top slab.1This specification is under the jurisdiction ofASTM Committee C27 on PrecastConcrete Products and is the direct responsibility of Subcommittee C27.30 on Waterand Wastewater Containers
13、.Current edition approved Oct. 15, 2007. Published November 2007. Originallyapproved in 1993. Last previous edition approved in 2007 as C 1227 07b.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandard
14、s 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-int.org.4Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New Yo
15、rk, NY 10036, http:/www.ansi.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.2.3 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, nt
16、ee or wall segment at or near the inletpipe of a tank designed to direct flow below the liquid surface.3.2.5 baffle, outlet, ntee 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 wa
17、ter to make concrete.3.2.7 connector, ndevice that provides a flexible sealbetween a pipe and the precast concrete tank.3.2.8 corrosion-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
18、and all permanentloads imposed on the structure (that is, soil).3.2.10 detention time, naverage length of time a unitvolume of 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, nma
19、ximum amount of liquid andsolids that can be contained in a tank under normal operatingconditions.3.2.12 effluent filter device, 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 fl
20、ushing cookingwastes; also known as a garbage disposal.3.2.14 inspection opening, nhole in the top slab used forthe purpose of 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
21、 up ofliquids and semibuoyant waste particles after the sludge andscum waste have separated and settled.3.2.17 live load, nloads 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
22、 will minimize the movementof liquid from one side of a precast concrete wall to theopposite side.3.2.19 owner, nis by definition, 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 n
23、ear thesurface of liquid, consisting of lighter-than-water materials,such as greases and soaps.3.2.22 sealed joint, njoint that 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 sew
24、age is received and retained, and fromwhich the liquid effluent, which is comparatively free fromsettleable and floating solids, 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-resist
25、ant materials used to connect horizontal piping withvertical piping and used to provide access for cleaning piping.4. Ordering 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 t
26、o 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 litres.4.1.4 Special cement requirements including moderatesulfate-resisting cement, Specification C 150 Type II, or highlysulfate-resisting cement, Specification C 150, Type
27、 V. If thepurchaser does not stipulate, the manufacturer shall use anycement meeting the requirements of Specification C 150 orC 595.4.1.5 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 surfa
28、ce, and ground water level.4.1.7 Testing for water leakage shall not be required at thejob site unless specifically required by the 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
29、-ments of Specification C 150 or shall be portland blast-furnaceslag cement or portland-pozzolan cement conforming to therequirements of Specification C 595.5.2 AggregatesAggregates shall conform to SpecificationC33and lightweight aggregates shall conform to SpecificationC 330, except that the requi
30、rements for grading shall not apply.5.3 WaterWater used in mixing concrete shall be cleanand free of injurious amounts of oils, acids, alkalies, salts,organic materials, or other substances that will be incompatiblewith concrete or steel.5.4 AdmixturesAdmixtures, when used, shall conform toSpecifica
31、tion C 494 or Specification C 618 and shall not beinjurious to other products used in the concrete.5.4.1 Air-Entraining AdmixturesAir-entraining admix-tures conforming to Specification C 260 shall be used whenthere is a risk that the concrete will be exposed to freezing andthawing. Then the concrete
32、 mixture shall contain 5.5 6 1.5 %air by volume as determined by Test Method C 231.5.5 Steel ReinforcementSteel reinforcement shall con-form to Specification A 82/A 82M or A 496/A 496M for wire,Specification A 185/A 185M or A 497/A 497M for wire fabric,or Specifications A 615/A 615M, A 706/A 706M,or
33、A 996/A 996M for steel reinforcement bars.5.5.1 Locating ReinforcementReinforcement shall beplaced in the forms as required by the design.5.5.2 Holding Reinforcement in Position During PouringPlacementReinforcement must be securely tied in place tomaintain position during concrete placing operations
34、. Chairs,bolsters, braces, and spacers in contact with forms shall have acorrosion-resistant surface.C 1227 07c25.6 Concrete MixturesThe aggregates, cement, and watershall be proportioned and mixed to produce a homogeneousconcrete meeting the requirements of this specification, and inaccordance with
35、 Specification C 94/C 94M or SpecificationC 685/C 685M.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. Form releasing agents usedshall
36、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 precast concrete sections shall b
37、e 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, which shall be specified by thep
38、urchaser. Concrete compressive strength tests shall be con-ducted in accordance with Test Method C 39/C 39M.5.11 FibersPolypropylene or polyolefin fibers are permit-ted, at the manufacturers option, in precast concrete septictanks as a nonstructural manufacturing material. Only Type IIIconforming to
39、 the requirements of Specification C 1116 shallbe accepted.5.12 SealantsFlexible sealants used in the manufactureand installation of tanks shall conform to Specification C 990.Rigid (mortar) sealing of tank sections is not permitted.6. Structural Design Requirements6.1 Structural design of septic ta
40、nks shall 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
41、 Method is 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
42、when subjected to anticipated earth and hydrostaticpressures when the tanks are either full or empty.6.1.4 After conditions are established, loads from PracticeC 890 shall be used for design. Unless heavier live loads areexpected, the minimum live load at the surface for design shallbe 300 lbf/ft2(1
43、4 kPa).6.1.5 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) fo
44、r designs shall 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 e
45、quipment shall 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 fol
46、lowing mini-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/s
47、eat)Additional 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 least1
48、212 % 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. (1800 mm)unless otherwise approved or required by lo
49、cal codes orjurisdiction.7.3 Compartments:7.3.1 The septic tank system shall include two compart-ments unless otherwise approved by local codes or jurisdiction.The two-compartment dividing wall is to be monolithicallycast or placed secondarily utilizing a non-sealed joint with thetank body.7.3.2 One double unit or two single compartment units inseries are acceptable.7.3.3 The first compartment shall have a liquid volume ofapproximately two thirds of the liquid volume of the entirecontents of the system.7.3.4 The transfer port between c
