1、Designation: C890 12C890 13Standard Practice forMinimum Structural Design Loading for Monolithic orSectional Precast Concrete Water and WastewaterStructures1This standard is issued under the fixed designation C890; the number immediately following the designation indicates the year oforiginal adopti
2、on or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice describes the minimum loads to be applied when designing mon
3、olithic or sectional precast concrete water andwastewater structures with the exception of concrete pipe, box culverts, utility structures, and material covered in SpecificationC478.1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathemat
4、icalconversions to SI units that are provided for information only and are not considered standard.1.3 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 healt
5、h practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C478 Specification for Precast Reinforced Concrete Manhole Sections2.2 AASHTO Standard:Standard Specifications for Highway Bridges, 16th Edition32.3 ACI Standard:ACI 318 Build
6、ing Code Requirements for Reinforced Concrete43. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 above ground structuresall structures with their base at or above ground.3.1.2 bearing loadsthe foundation pressure reaction to all other loads acting on the structure.3.1.3 below gro
7、und structuresall structures other than those with their base at or above ground.3.1.4 dead loadsthe mass of the structure and all permanent loads imposed on the structure.3.1.5 equipment loadsloads induced into the structure by equipment installed on mounting devices cast into the structure.3.1.6 h
8、ydrostatic loadsall pressures due to the weight of water or other liquids.3.1.7 lateral earth loadsthe lateral pressure due to the effective weight of adjacent earth backfill.3.1.8 lifting loadsthe forces induced into the structure during handling at the precast plant and the construction site.3.1.9
9、 surcharge loadsthe lateral pressure due to vertical loads superimposed on the adjacent earth backfill.3.1.10 traffc loadsall loads superimposed on the structure or adjacent earth backfill due to vehicles or pedestrians.1 This practice is under the jurisdiction of ASTM Committee C27 on Precast Concr
10、ete Products and is the direct responsibility of Subcommittee C27.30 on Water andWastewater Containers.Current edition approved Sept. 15, 2012Jan. 15, 2013. Published October 2012February 2013. Originally approved in 1978. Last previous edition approved in 20112012as C890 06 (2011). 12. DOI: 10.1520
11、/C0890-12.10.1520/C0890-13.2 For referencedASTM standards, visit theASTM 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 Available from American Associat
12、ion of State Highway and Transportation Officials (AASHTO), 444 N. Capitol St., NW, Suite 249, Washington, DC 20001,http:/www.transportation.org.4 Available from American Concrete Institute (ACI), P.O. Box 9094, Farmington Hills, MI 48333-9094, http:/www.concrete.org.This document is not an ASTM sta
13、ndard 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 appropriate. In all cas
14、es 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 States13.1.11 water and wastewater structuressolar heating reservoirs, septic tanks, ci
15、sterns, holding tanks, leaching tanks, extendedaeration tanks, wet wells, pumping stations, grease traps, distribution boxes, oil-water separators, treatment plants, manure pits,catch basins, drop inlets, and similar structures.4. Significance and Use4.1 This practice is intended to standardize the
16、minimum loads to be used to structurally design a precast product.4.2 The user is cautioned that he must properly correlate the anticipated field conditions and requirements with the design loads.Field conditions may dictate loads greater than minimum.5. Design Loads5.1 Dead Loads:5.1.1 Permanent ve
17、rtical loads typically include the weight of the road bed, walkways, earth backfill, and access opening covers.5.1.2 Recommended unit weights of materials for design are shown in Table 1.5.2 Traffc Loads:5.2.1 The vehicle and pedestrian loadings are shown in Table 2.5.2.2 The arrangement and spacing
18、 of vehicle wheels are shown in Fig. 1 and Fig. 2.5.2.3 Distribution of Wheel Loads through Earth Fills:5.2.3.1 For structures where vehicle wheels contact the top surface of the structure, the vehicle wheel loads will be distributedover an area as shown in Fig. 3. The loaded area will be:A 5W 3L (1
19、)where:A = wheel load area, ft2 (m2),W = wheel width, ft (m), andL = wheel length, ft (m).5.2.3.2 For below ground structures where backfill separates the vehicle wheels and the top surface of the structure, the vehiclewheel loads will be distributed as a truncated pyramid as shown in Fig. 4.The loa
20、ded area will be:A 5W11.75 H! 3L11.75 H! (2)where:A = wheel load area, ft2 (m2),W = wheel width, ft (m),L = wheel length, ft (m), andH = height of backfill between wheels and structure, ft (m).5.2.3.3 When several distributed wheel load areas overlap, the total wheel load will be uniformly distribut
21、ed over a compositearea defined by the outside limits of the individual areas. Such a wheel load distribution is shown in Fig. 5.5.2.3.4 When the dimensions of the distributed load area or the composite distributed load area exceed the top surface area ofthe structure, only that portion of the distr
22、ibuted load within the top surface area will be considered in the design.5.2.4 The effects of impact will increase the live wheel loads designated as A-16, A-12, and A-8 as shown in Table 3.TABLE 1 Unit Weights of MaterialsMaterial Weight, lbf/ft3 (N/m3)Concrete (plain or reinforced) 150 (23 600)Lig
23、htweight Concrete (reinforced) 100 to 130 (15 700 to 20 400)Cast Iron 450 (70 700)Steel 490 (77 000)Aluminum 175 (27 500)Earth Fill 100 to 150 (15 700 to 23 600)Macadam 140 (22 000)C890 132TABLE 2 Vehicle and Pedestrian Load DesignationsDesignation Load, max UsesA-16 (HS20-44)A 16 000 lbf (71 200 N)
24、 per wheel heavy trafficA-12 (HS15-44)A 12 000 lbf (53 400 N) per wheel medium trafficA-8 (H10-44)A 8 000 lbf (35 600 N) per wheel light trafficA-03 300 lbf/ft2 (14 400 Pa) walkwaysA The designations in parentheses are corresponding ASSHTO designations.Designation Load at A Load at B Load at Clbf N
25、lbf N lbf NA-16 (HS20-44)A 4 000 17 800 16 000 71 200 12 000 53 400A-12 (HS15-44)A 3 000 13 300 12 000 53 400 8 000 35 600A-8 (H10-44)A 2 000 8 900 8 000 35 600 6 000 26 700A The designations in parentheses are corresponding ASSHTO designations.FIG. 1 Single Vehicle Traffic Loads and SpacingFIG. 2 M
26、ultiple Vehicle SpacingFIG. 3 Wheel Load AreaFIG. 4 Distributed Load AreaFIG. 5 Composite Distributed Load AreaC890 1335.3 Hydrostatic Loads:5.3.1 The water pressure acting on any point on the outside surface of the structure is:PW 5W W 3HW (3)where:PW = hydrostatic pressure, lbf/ft2 (Pa),WW = unit
27、weight of water, lbf/ft3 (N/m 3), andHW = distance from the ground water surface to the point on the structure under consideration, ft (m).5.3.2 The liquid pressure acting on any point on the inside surface of the structure is:P L 5WL 3HL (4)where:PL = liquid pressure, lbf/ft2 (Pa),WL = unit weight
28、of the liquid, lbf/ft3 (N/m 3), andHL = distance from the liquid surface to the point on the structure under consideration, ft (m).5.4 Lateral Earth Loads:5.4.1 The lateral earth pressure on the walls of a buried structure for the portion of the walls above the ground water surfacewill be:PE 5K 3W E
29、 3HE (5)where:PE = lateral earth pressure, lbf/ft2 (Pa),K = coefficient of lateral earth pressure,WE = unit weight of the earth backfill, lbf/ft3 (N/m3), andHE = distance from the surface of the earth backfill to the point on the structure walls under consideration, ft (m).5.4.2 The lateral earth pr
30、essure on the walls of a buried structure for the portion of the walls below the ground water surfacewill be:PE 5K 3W E 3HE 2H W!#1K 3WE 2W W! 3HW# (6)where:PE = lateral earth pressure, lbf/ft2 (Pa),K = lateral earth pressure coefficient,WE = unit weight of the earth backfill, lbf/ft3 (N/m3),HE = di
31、stance from the surface of the earth backfill to the point on the structure under consideration, ft (m),WW = unit weight of water, lbf/ft3 (N/m3), andHW = the distance from the surface of the ground water table to the point on the structure under consideration, ft (m).5.4.3 Laboratory and field test
32、ing has shown that the value of the lateral earth pressure coefficient depends on the yielding ofthe wall of the structure relative to the earth backfill. Walls of sectional precast concrete structures can yield by rotating, translating,or deflecting. Walls of monolithic precast concrete structures
33、can yield by deflecting. The lateral earth pressure on a structure wherethe walls can yield sufficiently will be considered as the active pressure. The value of the lateral earth pressure coefficient for thiscondition can be estimated by Rankines equation of:KA 512 sin #/11 sin # (7)where:KA = activ
34、e earth pressure coefficient, and = internal friction angle of the earth backfill, degrees.The value of KA shall be as computed or 0.30, whichever is greater.5.5 Surcharge Loads:TABLE 3 Wheel Load Increases for ImpactHeight of Backfill Between Wheel and Structure Increase0 to 12 in. (0 to 305 mm) 30
35、 %13 to 24 in. (330 to 610 mm) 20 %25 to 35 in. (635 to 890 mm) 10 %36 in. (915 mm) or greater 0 %C890 1345.5.1 When traffic can come within a horizontal distance from the structure equal to one half of the height of the structure, alateral surcharge pressure will be applied to the wall of the struc
36、ture. Lateral surcharge pressures for the designated vehicle wheelloads are shown in Table 4.5.5.2 Lateral surcharge loads from traffic will be considered negligible below a vertical distance 8 ft (2.4 m) below the wheel.5.6 Lifting Loads:5.6.1 The lifting load induced into the structure will be not
37、 less than the total dead weight of the precast unit distributed overnot more than three lifting points.5.7 Cumulative Loadings:5.7.1 The cumulative vertical loading possible on the top or base of a structure are shown schematically in Fig. 6 and Fig. 7,respectively.5.7.2 The cumulative horizontal l
38、oadings possible on the walls of a structure are shown schematically in Fig. 8.6. Loading Combinations for Above Ground Structures6.1 The design load for the top of the structure will consider the cumulative effects of dead loads, snow loads, and either apedestrian live load if applicable, or a nomi
39、nal live load of 20 lbf/ft2 (958 Pa). Local area building codes will be used for snowloads.6.2 The design load for the walls of the structure will consider both of two individual load cases.6.2.1 Load Case A Load Case A will consider a structure full condition and will include only the internal hydr
40、ostatic loads.6.2.2 Load Case B Load Case B will consider a structure empty condition and will include either the effects of wind load orhorizontal vehicle impact if applicable. Local area building codes or a nominal external pressure of 30 lbf/ft2 (1436 Pa) will beused for wind loads.6.3 The design
41、 load for the base of the structure will consider the applicable individual load case.6.3.1 Load Case A Load Case A is an empty structure resting on the ground and will consist of a bearing load uniformlydistributed over the base.6.3.2 Load Case B Load Case B is a full structure raised above the gro
42、und and will include the cumulative effects of deadloads and internal hydrostatic loads.7. Loading Combinations for Below Ground Structure7.1 The design load for the top of the structure will consider the cumulative effects of dead loads, snow loads, and traffic loads.Local area building codes will
43、be used for snow loads.7.2 The design load for the walls of the structure will consider both of two independent load cases.7.2.1 Load Case A Load Case A is a structure full condition and will include the cumulative effects of maximum internalhydrostatic loads, minimum external hydrostatic loads, and
44、 minimum lateral earth pressure loads.7.2.2 Load Case B Load Case B is a structure empty condition and will include the cumulative effects of maximum externalhydrostatic loads, maximum lateral earth pressures, and lateral surcharge loads.7.3 The design load for the base of the structure will conside
45、r the cumulative effects of the bearing load and the externalhydrostatic load.8. Special Loading Considerations8.1 The structural design loading for unique applications will also consider thrust, vibration, and ice loads applicable.8.2 The structural design for below ground structures will also cons
46、ider buoyancy effects, if applicable, and proportion thestructure to assure an adequate flotation safety factor.8.3 The structural design loading will also consider the stresses due to the effects of concrete shrinkage and thermal movement.The reinforcing steel provided in areas of the structure sub
47、ject to such stresses will equal or exceed the minimum amounts requiredby the referenced reinforced concrete design standards in Section 4.8.4 Lifting inserts which are embedded or otherwise attached to the structure will be designed for four times the maximum loadtransmitted to the inserts.TABLE 4
48、Lateral Surcharge PressuresDesignation Lateral Surcharge PressureA-16 (HS20-44)A 80 lbf/ft2 (3830 Pa) per wheelA-12 (HS15-44)A 60 lbf/ft2 (2873 Pa) per wheelA-8 (H10-44)A 40 lbf/ft2 (1915 Pa) per wheelA The designations in parentheses are corresponding ASSHTO designations.C890 135FIG. 6 Cumulative V
49、ertical Top LoadsFIG. 7 Cumulative Vertical Base LoadsC890 136ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin 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 and must be reviewed every five years andif not revised, eith
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