1、Designation: B 789/B 789M 99 (Reapproved 2005)Standard Practice forInstalling Corrugated Aluminum Structural Plate Pipe forCulverts and Sewers1This standard is issued under the fixed designation B 789/B 789M; the number immediately following the designation indicates the yearof original adoption or,
2、 in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.A superscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice covers procedures, soils, and soil place-ment for the proper inst
3、allation of corrugated aluminumstructural plate culverts and sewers in either trench or embank-ment installations. A typical trench installation is shown in Fig.1, and a typical embankment (projection) installation is shownin Fig. 2. Structural plate structures as described herein arethose structure
4、s factory fabricated in plate form and boltedtogether on site to provide the required shape, size, and lengthof structure. This practice applies to structures designed inaccordance with Practice B 790/B 790M.1.2 The values stated in either inch-pound units or SI unitsare to be regarded separately as
5、 standard. Within the text, theSI units are shown in brackets. The values stated in eachsystem are not exact equivalents; therefore, each system shallbe used independently of the other. Combining values from thetwo systems may result in nonconformance with the standard.1.3 This standard does not pur
6、port 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 determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2B
7、746/B 746M Specification for Corrugated Aluminum Al-loy Structural Plate for Field-Bolted Pipe, Pipe-Arches,and ArchesB 790/B 790M Practice for Structural Design of CorrugatedAluminum Pipe, PipeArches, and Arches for Culverts,Storm Sewers, and Other Buried ConduitsD 698 Test Method for Laboratory Co
8、mpaction Character-istics of Soil Using Standard Effort (12 400 ft-lbf/ft600kN-m/m)D 1556 Test Method for Density and Unit Weight of Soil inPlace by the Sand-Cone MethodD 1557 Test Method for Laboratory Compaction Character-istics of Soil Using Modified Effort (56 000 ft-lbf/ft32700kN-m/m3)D 2167 Te
9、st Method for Density and Unit Weight of Soil inPlace by the Rubber-Balloon MethodD 2487 Classification of Soils for Engineering Purposes(Unified Soil Classification System)D 2922 Test Methods for Density of Soil and Soil-Aggregate in Place by Nuclear Methods (Shallow Depth)1This practice is under t
10、he jurisdiction of ASTM Committee B07 on LightMetals and Alloys and is the direct responsibility of Subcommittee B07.08 onAluminum Culvert.Current edition approved Apr. 1, 2005. Published April 2005. Originallyapproved in 1988. Last previous edition approved in 1999 as B 789/B 789M 99.2For reference
11、d ASTM standards, visit the ASTM website, 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.FIG. 1 Typical Trench InstallationFIG. 2 Typical Embankment (Projection) In
12、stallation1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.D 2937 Test Method for Density of Soil in Place by theDrive-Cylinder Method3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 arch, nsegment of a circular
13、shape spanning an openinvert between the footings on which it rests.3.1.2 bedding, nearth or other material on which a pipe issupported.3.1.3 haunch, nportion of the pipe cross section betweenthe maximum horizontal dimension and the top of the bedding.3.1.4 invert, nlowest point on the pipe cross se
14、ction; also,the bottom portion of a pipe.3.1.5 pipe, nconduit having a full circular shape; also, ina general context, all structure shapes covered by this specifi-cation.3.1.6 pipe-arch, npipe with an approximate semicircularcrown, small-radius corners, and large-radius invert.3.1.7 underpass, npip
15、e with an approximate semicircularcrown, large-radius sides, small-radius corners between sidesand invert, and large-radius invert.4. Significance and Use4.1 Corrugated aluminum structural plate pipe functionsstructurally as a flexible ring that is supported by and interactswith the compacted surrou
16、nding soil. The soil placed aroundthe structure is thus an integral part of the structural system. Itis therefore important to ensure that the soil structure is madeup of the acceptable material and well-constructed. Fieldverification of soil structure acceptability using Test MethodsD 1556, D 2167,
17、 D 2922,orD 2937, as applicable, and com-paring the results with Test Methods D 698 or D 1557,inaccordance with the specifications for each project, is the mostreliable basis for installation of an acceptable structure. Therequired density and method of measurement are not specifiedby this practice
18、but must be established in the specifications foreach project.5. Trench Excavation5.1 To obtain the anticipated structural performance ofstructural plate structures, it is not necessary to control trenchwidth beyond the minimum necessary for proper assembly ofthe structure and placement of the struc
19、tural backfill. However,the soil on each side beyond the excavated trench must be ableto support anticipated loads. When a construction situationcalls for a relatively wide trench, it may be made as wide asrequired for its full depth, if so desired. However, trenchexcavation must be in compliance wi
20、th any local, state, andfederal codes and safety regulations.6. Foundation6.1 The supporting soil beneath the structure must provide areasonably uniform resistance to the imposed load, bothlongitudinally and laterally. Sharp variations in the foundationmust be avoided. When rock is encountered, it m
21、ust beexcavated and replaced with soil. If the structure is to be placedon a continuous rock foundation, it will be necessary to providea bedding of soil between the rock and the structure. See Fig.3.6.2 Lateral changes in foundation should never be such thatthe structure is firmly supported while t
22、he backfill on eitherside is not. When soft material is encountered in the foundationand must be removed to maintain the grade on the structure,then it must be removed, usually for a minimum of threestructure widths. See Fig. 4. A smaller width of removal cansometimes be used if established by the e
23、ngineer.6.3 Performance of buried structures is enhanced by allow-ing the structure to settle slightly relative to the columns ofearth alongside. Therefore, when significant settlement of theoverall foundation is expected, it is beneficial to provide ayielding foundation under structural plate struc
24、tures.Ayieldingfoundation is one that allows the structure to settle vertically bya greater amount than the vertical settlement of the columns ofearth alongside. It can usually be obtained by placing beneaththe structure a layer of suitable thickness of compressible soil,less densely compacted than
25、the soil alongside. This is particu-larly important on structures with relatively large-radius invertplates.d =12 in./ft. 40 mm/m of fill over pipe, with a 24-in. 600 mm maximum.NOTESection B-B is applicable to all continuous rock foundationsFIG. 3 Foundation Transition Zones and Rock FoundationsFIG
26、. 4 Soft Foundation TreatmentB 789/B 789M 99 (2005)26.4 For all structures with relatively small-radius cornerplates adjacent to large-radius invert plates (such as pipe-arches or underpass structures), excellent soil support must beprovided adjacent to the small-radius corner plates by both thein-s
27、itu foundation and the structural backfill. See Fig. 4 andFig. 5. A yielding foundation must be provided beneath theinvert plates for such structures when soft foundation condi-tions are encountered.7. Bedding7.1 In most cases, structural plate structures may be as-sembled directly on in-situ materi
28、al fine-graded to properalignment and grade. Take care to compact the materialbeneath the haunches prior to placing structural backfill. Forstructures with relatively small-radius corner plates adjacent tolarge-radius invert plates, it is recommended to either shape thebedding to the invert plate ra
29、dius or fine-grade the foundationto a slight v-shape. The soil adjacent to the corners must be ofan excellent quality and highly compacted to accommodate thehigh reaction pressures that can develop at that location. SeeFig. 5.7.2 Structures having a span greater than 15 ft 4.5 m or adepth of cover g
30、reater than 20 ft 6 m should be provided witha shaped bedding on a yielding foundation. The bedding shouldbe shaped to facilitate the required compaction of the structuralbackfill under the haunches. A shaped bedding on a yieldingfoundation is always required under structures with small-radius corne
31、r plates adjacent to large-radius invert plates.7.3 Material in contact with the pipe must not contain rockretained on a 3-in. 75-mm diameter ring, frozen lumps,chunks of highly plastic clay, organic matter, corrosive mate-rial, or other deleterious material.8. Assembly8.1 Structural plate structure
32、s are furnished in componentsof plates and fasteners for field assembly. These componentsare furnished in accordance with Specification B 746/B 746M.Plates are furnished in a 4 ft, 6 in. 1372 mm width andmultiple lengths, preformed and punched for assembling intothe required structure shape, size, a
33、nd length. The plate lengthsform the periphery of the structure. Arrange the single widthand the multiple lengths to allow for staggered, transverseseams to avoid four-plate laps. The fabricator of the structuralplate shall furnish an assembly drawing showing the locationof each plate by width, leng
34、th, thickness, and curvature. Theplates must be assembled in accordance with the fabricatorsdrawing.8.2 For structures with inverts, assembly shall begin withthe invert plates at the downstream end. As the assemblyproceeds upstream, plates that fall fully or partly below themaximum width of the stru
35、cture are lapped over the precedingplates to construct the transverse seams.8.3 Arches on Footings:8.3.1 FootingsArches have no integral invert and usuallyrest in key ways cast into footings. Key ways must beaccurately set to span, line, and grade, as shown in the plansand specifications. When the a
36、rch is not a half circle, the keyway must be angled (rotated) or sized to allow proper entranceof the plate. All pertinent dimensions must be shown on thedrawings.8.3.2 AssemblyFor arch structures, assembly typicallybegins at the upstream end and proceeds downstream, witheach succeeding plate lappin
37、g on the outside of the previousplate. There may be cases where it is more advantageous tostart assembly at some other point along the length of thestructure, such as is in the case where an elbow is involved.During the erection of the ring, plates are not self-supportingand must be temporarily supp
38、orted. If the size of the key waysis such that the plates may move during backfilling, the platesmust be temporarily blocked in the key ways to maintain span.Assemble as few plates as practical. Start with a row of severalplates along both of the footings. Before finishing the bottomrow of plates, s
39、tart at the end of the structure with the next rowof plates. Before reaching the end of the first row of plates, startagain at the end of the structure with the next row of plates.Continue this process until the first ring is closed at its top, andthen continue assembling all rows in this same manne
40、r. Thestructure will have a “stair step” appearance as a result of thisprocedure. This practice helps to hold the structures shape.8.4 Generally, structural plate should be assembled with asfew bolts as practical. These bolts should be placed loose andremain loose until the periphery has been comple
41、ted for severalplate lengths. However, on large structures, it is practical toalign bolt holes during assembly and tighten the bolts tomaintain structure shape. After the periphery of the structure iscompleted for several plate lengths, all bolts may be placed andtightened. Correct any significant d
42、eviation in the structureshape before tightening bolts (see Section 10). It is advisablenot to tighten bolts on the loosely assembled structure within adistance of 30 ft 9 m of where plate assembly is ongoing. Allbolts shall be tightened using an applied torque of between 100and 150 ftlbf 135 and 20
43、5 Nm. It is important not toover-torque the bolts.FIG. 5 Bedding and Corner Zone Treatment for Large-RadiusInvert Plate StructuresB 789/B 789M 99 (2005)38.5 Standard structural plate structures, because of thebolted construction, are not intended to be watertight. Onoccasions where a degree of water
44、tightness is required, it ispractical to introduce a seam sealant tape within the boltedseams. The tape shall be wide enough to effectively cover allrows of holes in plate laps, and of the proper thickness andconsistency to effectively fill all voids in plate laps. Generalprocedures for installing s
45、ealant tape are as follows: Onlongitudinal seams, prior to placing the lapping plate, roll thetape over the seam and work into the corrugations. Do notstretch the tape. Remove any paper backing prior to making upthe joint. Seal transverse seams in a like manner with tape. Atall points where three pl
46、ates intersect, place an additionalthickness of tape for a short distance to fill the void caused bythe transverse seam overlap. It is most practical to punch thetape for bolts with a hot spud wrench or sharp tool.At least twotightenings of the bolts will usually be necessary to accomplishthe requir
47、ed torque.9. Structural Backfill Material9.1 Structural backfill is that material that surrounds thepipe, extending laterally to the walls of the trench or to the fillmaterial for embankment construction, and extending verti-cally from the invert to an elevation of 1 ft 300 mm or18 thespan, whicheve
48、r is greater, over the pipe. The necessary widthof structural backfill depends on the quality of the trench wallor embankment material, the type of material and compactionequipment used for the structural backfill, and in embankmentconstruction, the type of construction equipment used tocompact the
49、embankment fill. The width of structural backfillshall meet the requirements given in Table 1.9.2 Structural backfill material shall be readily compactedsoil or granular fill material. Structural backfill may be exca-vated native material, when suitable, or select material. Selectmaterial such as bank-run gravel, or other processed granularmaterials (not retained on a 3-in. 75-mm diameter ring) withexcellent structural characteristics, is preferred. Desired endresults can be obtained with such material with a minimum ofcompactive effort over
