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Technical Data
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IntroductionAveng Manufacturing Infraset manufacturesreinforcedconcretepipesusingtwowell-knownproduction processes: roller suspension andautomated vertical casting using high strength,highdurabilityconcrete.Boththeseprocessesareusedworldwideandareacknowledgedtobeidealforconcretepipemanufacturing.
All the manufacturing processes are doneundercarefullycontrolledconditionsusingadvancedtechnologyandequipment.Theseprocessesprovideflexibility for the manufacturing of tailormade wallthicknessesforspecialloadandstrengthrequire-ments.
If corrosion problems are anticipated, AvengManufacturing Infraset has severalmethods ofprolonging the life of the concrete pipe. Thesubstitution of the siliceous aggregates withcalcareousaggregatesresultsintheextendedlifeoftheconcretepipe.AnHDPElinercanalternativelybeadded to theboreof thepipe to prevent thesulphuricacidsfromcomingintocontactwiththeconcretesurface.
CLASSIFICATIONOFPIPES
TypesofpipeAvengManufacturingInfrasetoffersalargerangeofpipesreadilyavailableinnominallengthsof2.5mandalsohalf-lengthsonspecialarrangement.
Pipesrangingfrom300to1800withInterlockingogeejoints,300to1800pipeswithSpigotandSocket joints and 900 to 1800 pipes withIn-the-Walljointsareallproducedinthreestrengthclasses.
Jacking pipes are manufactured only in class100D and vary in size from 840 to 2500.StrongerpipescapableofcarryinghigherD-loadsaremanufacturedonrequest.
All Aveng Manufacturing Infraset pipes bear theSANSmark andare designed,manufacturedandtestedinaccordancewithSANS677.
SC (Stormwater Culvert) pipes are manufacturedwithanon-watertight,interlockingogeejoint.
Thesewerandirrigation(SI)pipesaremanu-facturedusingdolomiticaggregatesandhaveawatertightSpigotandSocketorIn-the-Walljoint.Sewer pipeswith a sacrificial layer (WSL) aremanufacturedtotheSABS1200LDrequirementswithanadditional15mmcoverforpipesrangingfrom300to1050and20mmforpipes12001800.T2andT4pressurepipes,testedto2and4barrespectivelyareavailableonrequest.
Spigot and Socket and In-the-Wall joint pipes arejoinedandsealedusingeitherarollingrubberoraslidingrubberringrespectively.Theslidingrubberringisinstalledusingasoftsoaplubricant.
Typesofjoints
StrengthofpipesTwostrengthtestsaredoneonAvengManufacturingInfrasetpipes.ThefirstisacrushingtestonboththeSCandSI pipes, and the second is ahydraulicpressure test only on theSI pipes. The two edge-bearingcrushingtest isdonetoaproof loadandalso to an ultimate load 25% greater than theproof load.The proof load is determined by theclassof pipemultipliedby thenominal diameterofthepipe.Theproofloadtestcanbedefinedasa line load that a pipemust resistwithout thedevelopment of crack widths exceeding 0.25mmoveralengthofmorethan300mm.Theultimateloadisthemaximumlineloadthatthepipemustsupportinthesametest.
InterlockingOgeeJoint Spigot&SocketJoint
ButtJoint In-the-WallJoint
PRECAST CONCRETEPIPES
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AvengManufacturingInfrasetpipesbeartheSANSmarkandaredesigned,manufacturedandtestedinaccordancewithSANS677.
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Embankment condition: Class C
ThefollowingtablesgivethepipestrengthrequirementsintermsofD-Loadsforpipeslaidinatrenchcondition,withtrenchwidthsasperSANS1200DB,andinembankmentcondition,bothwithNB36trafficloading.ThesetablesmeettheD-Loadrequirementsforgeneralsiteconditions.
Loadclassifications
Note:D=NominalDiameterinmetres.Example: A1500mm75Dpipemustresist: ProofLoad=75x1.5=113kN/m UltimateLoad=75x1.5x1.25=140kN/mAllSIpipesaretestedto1,4barandpassesthetestifthepipewithstands thepressure forat least twominuteswithoutanysignofleakage.
LoadsonpipesWorking loads on pipes consist of primary and secondaryloads. The primary loads that the pipesmust carry are; themassof earth fill above thepipe, traffic loadingand internalpressures.Thesecondaryloadsresultfromsoilmovementandtemperatureeffectsthatinfluencethepipeline.Thesesecondaryloadsareaccommodatedbytheflexiblepipejoints.
Earth loadsaredeterminedusingtheMarstonandSpanglertheoryandaredependantuponthetypeofinstallation,typeofbackfillmaterialandheightoffill.Thetwoinstallationconditionsaretrenchandembankment.
Traffic loads are dependant upon thewheel loads, spacingandcontactareas,andthedistributionofthesethroughthefill.ThestandardtrafficloadsapplicabletonationalhighwaysaregivenintheTMH7:Codeofpracticeforthedesignofhighwaybridgesandculverts inSouthAfrica.AvengManufacturingInfraset pipes are designed for a NB36 load, which equalsanaxle loadof360kNora90kNwheel load.Theeffectivecontactareaoftheloadisasquareofsize0.3mx0.3m.
Bedding factor refers to the amount bywhich the beddingenhancestheload-carryingcapacityofthepipe.Thebeddingfactorisdefinedastheratiobetweenthesupportingstrengthof theburiedpipe to the strengthof thepipeasdeterminedin the two-edgebearing test.Thebeddingofapipeconsistsofacradleofgranularmaterialunderneaththepipe,whichsupports itandtransfers the loadto the foundation.Beddingfactorsaredividedintofourclassesandaredeterminedbytheangleofsupportandtypeofthebeddingmaterial.
Standardbeddingclassesandfactors
InstallationconditionsTrenchconditionoccurswhen thepipe isplaced ina trenchcut intonaturalgroundlevelandthenbackfilledwithsuitablematerial.
Trench condition: Class B
Trench condition: Class C
In the embankment condition the pipe is installed at groundlevelandisbackfilledwithsuitablematerial.
Technical Data
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50D 50xD 50xDx1.25 0.149 13.2 7
75D 75xD 75xDx1.25 0.255 21.8 7
100D 100xD 100xDx1.25 0.425 36.0 7
Wolf ACSR 18.13 0.726 69.2 37
Bear ACSR 23.45 1.213 111.1 37
7/3.35 Steel 10.23 0.496 67.9 7
7/4.0 Steel 12.24 0.712 96.8 7
19/2.65 Steel 13.55 0.849 114 19
Class of Pipe Proof Load Ultimate Load Weight per m(kg/m)
Ultimate tensilestrength (kN)
Total strands
Beddingangle
A 2.8 3.8 120 13.2 7
B 2.0 2.5 180 21.8 7
C 1.5 2.0 90 36.0 7
D 1.1 N/A 0 69.2 37
Bear ACSR 23.45 1.213 111.1 37
7/3.35 Steel 10.23 0.496 67.9 7
7/4.0 Steel 12.24 0.712 96.8 7
19/2.65 Steel 13.55 0.849 114 19
Class Trench Embankment Bedding Angle