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.

PipesrangingfromØ300toØ1800withInterlockingogeejoints,Ø300toØ1800pipeswithSpigotandSocket joints and Ø900 to Ø1800 pipes withIn-the-Walljointsareallproducedinthreestrengthclasses.

Jacking pipes are manufactured only in class100D and vary in size from Ø840 to Ø2500.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) aremanufacturedtotheSABS1200LDrequirementswithanadditional15mmcoverforpipesrangingfromØ300toØ1050and20mmforpipesØ1200–Ø1800.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