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Page 1: Engineering / Maintaining Documentation

Engineering / Maintaining Documentation

Drawings and Maintaining Proper Documentation: IftheexistingLARCdrawingsarenotavailable,newLARCdrawingsshowingtheloadcapacityoftherepaired systemmustbecreated.TheSupervisingEngineershouldapprovesuchdrawingsbeforerepairsarebegun. LARCdrawingsshouldprovideclearinformationdefiningtherepairorreplacement,aswellas,configurations ofbaysorsectionsaffectedbytherepairorreplacement.

NoticeshouldbeconspicuouslydepictedonLARCdrawingsshowingthattheSupervisingEngineeristo evaluateanydeviationsfromthedrawingsandthatanydeviationmayimpairthesafetyoftheracksystem. (RMI/ANSIMH16.1[1],Section1.4.5).

An example LARC Drawing. *Note that design loads and beam elevations are clearly identified

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Load Capacity Plaque: AsoutlinedinRMI/ANSIMH16.1[1],Section1.4.2,theOwnerisresponsibletoensurethatloadcapacity plaquesareconspicuouslydisplayedinoneormoreprominentlocations.Ifthereareanychangestotherack configuration,thecapacityplaquesmustbeupdatedandreinstalled.

An Example of an RMI Load Plaque

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Technical Requirements: TheSupervisingEngineershallreviewthemaximumloadingcapabilitiesofthesystemwiththeOwner Operator.Ifappropriate,theSupervisingEngineershoulddetermineallexternalloadingrequirementsofthe rackstructure,includingproductload,windload,snowload,rainonsnowsurcharge,snowdrifting,seismic loadanddeadandliveloadfromstructuressupportedbythestoragerackandmore.Thenecessarystrength andstiffnessofthemembersandconnectionsshallbedeterminedbystructuralanalysisfortheappropriate loadcombinations(ASDorLRFD,asrequiredbyRMI/ANSIMH16.1[1]Section2.1or2.2,respectively.

Thecomponentsaffected,bytherepairorreplacement,shallmeetallthematerialanddesignrequirements oftheRMI/ANSIMH16.1Specification[1]andCommentary,whichdetailscomponentdesignrequirements. ThefollowinginformationinthisguidelineisforsomecomponentsthatarenotmentionedintheRMI/ANSI MH16.1Specification[1],butisimportantanduniquetotherepairofstorageracks.

Whentestingisrequired,representativesamplesofspecificcomponentsfromtheexistingsystembeing repairedshallbeusedwiththenewrepaircomponentinaprocedurethatisapprovedandoverseenbythe SupervisingEngineer.ThistestingmaybedoneinanyfacilityacceptabletotheSupervisingEngineer,andthe testingrecordsshallbemaintainedbytheSupervisingEngineer.

Column: ColumnSplice:

Ifitisnecessarytorepairacolumnsegmentwithanewsection,asplicemaybeusedtojointhetwo components.Thecontinuityoftheloadpathacrossthissplicejointiscriticaltothestructuralintegrityofthe repair.

ThecolumnsplicemustmeettheloadingrequirementsoftheapplicableloadingcombinationsinRMI/ANSIMH 16.1[1]Section2.1orSection2.2.Thespliceconnectionshallbeevaluatedforthefollowingfactorsincluding, butnotlimitedto:columnaxialforce,flexuralbuckling,torsionalbuckling,flexural-torsionalbuckling,column axialslipresistance,thecolumnbendingstrength,thecolumnbendingstiffness.

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Column: ColumnBaseplate

Acolumnbaseplatemayhavetoberepairedwithanewplatebecausethecolumnmustbere-anchoredand oldholelocationsarenolongeravailable.Thebendingstiffnessofthebasejointmaybecriticaltothesuccess oftherepair.

Thecolumnbaseplatemustbeshowntomeettheloadingrequirementsoftheapplicableloading combinationsinRMI/ANSIMH16.1[1]Section2.1orSection2.2.Thebaseconnectionshallbeevaluatedfor thefollowingfactorsincluding,butnotlimitedto:thecolumndownwardaxialforce,thecolumnuplift,the basejointbendingstrengthandthebasejointbendingstiffness.

Ifreplacementanchorscannotbelocatedinthesameplacerelativetothecolumn,anewlocationmustbe designedandtested.Replacementanchorsshallbelocatedinthesameholeornotlessthan3timesthelarger anchordiameterfromexistinganchorholeswhethertheholesareemptyorcontaintheremnantsofold anchors.Ifexistinganchorholesarefilledwith“dry-packmortar”andthemortarhassetfornotfewerthan7 days,replacementanchorsshallbeplacednotlessthan1.5timesthediameterofthelargestanchorfrom existingholes.

Whenweldingnewbaseplatesontoexistingframes,fieldweldingrisksdiscussedinAppendix1oftheRMI RackRepairGuidelinesshouldbecarefullyconsidered.

Bracing Continuity: Originalframebracinggenerallyprovidesacontinuousloadpathtothesupports.Repairofthatbracingmustbeshowntoestablishasatisfactoryreplacementoftheoriginalloadpath.

ThedesignoftherepairedbracingsystemwithanevaluationoftherepairkitandtheexistingstructuremustensurethatstabilityandforcerequirementsmeetRMI/ANSIMH16.1[1],Section2.4.Framebracinganditsconnectionstothecolumnmustbeshowntohavethenecessarystrengthandstiffnesstosupportthecolumnaxialandbendingload.Allframebracingthatisreplacedorrepaired,mustbecapableofcarryingthisload.

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Bracing Continuity (Continued): Considerationsmustbegiventocompressionbracingmembersthathavediscontinuitiesorsplices.

Shelf Beams: ShelfConnection Theshelfbeam-to-columnconnectorofconventionalrackingistheprimaryjointthatstabilizesthestorage rackcolumnsinthedown-aisledirection.Theseconnectionsvarywidelyfrommanufacturertomanufacturer. EachoriginalequipmentmanufacturerhastesteditsconnectorwithitscolumninaccordancewithRMI/ANSI MH16.1[1].

Ifashelfmustbereplaced,theSupervisingEngineershallobtain(ordevelopthroughtesting)thebeam-to columntestresultsthatareforthespecificcombinationbeingused,andshallincorporatethatdataintothe designoftherepairsolution.

LateralBracingBeam Beams(particularlyopensections)thatarebentabouttheirmajoraxisaresubjecttolateralbucklingofthe compressionflange.Ifthereplacementbeamsareopensections,thedesignshallaccountforthisbuckling,or adequatelybracethecompressionflange.


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