Effectoflateralimpactloadsonfailureofpressurizedpip193EffectoflateralimpactloadsonfailureofpressurizedpipelinessupportedbyfoundationCSNg1andWQShen21JPKennyLtd(formerlyUniversityofPortsmouth),Staines,UK2DepartmentofMechanicalandDesignEngineering,UniversityofPortsmouth,Portsmouth,UKThemanuscriptwasreceivedon1March2021andwasacceptedafterrevisionforpublicationon23June2021.DOI:10.1243/0954408JPME97Abstract:Thedynamicinelasticresponseandfailurepredictionofpipelinesunderlateralmassimpactatthemid-spanpositionarepresentedinthisarticle.Atotalof52impacttestswerecarriedoutonseamlessmildsteelpipeswithdifferentinternalpressurelevelsandfoundationsupports.Criticalinitialimpactenergieswereobtainedforeachgroupofpipespecimenswithdifferentinternalpressurelevelsandfoundationsupports.Numericalsimulationsoftheexperimentaltestswerecarriedoutusingthree-dimensionaldynamicnon-linearniteelementanalysis,wherebothgeometricalandmaterialnon-linear-itieswereconsidered.Goodagreementswereachievedbetweentheimpacttestsresultsandthenumericalpredictions.Ithasbeenfoundthattheinuencesoftheinternalpressureandthefoundationonthecriti-calinitialimpactenergyaresignicant.Thecriticalinitialimpactenergyismuchlesssensitivetointernalpressureforthepipeswithafoundationthanthosewithoutafoundation.Keywords:pipeline,foundation,niteelementanalysis,impact,pressure1INTRODUCTIONResearchonpipelineshasbeencarriedoutforafewdecades.Muchworkhasrecentlybeendoneinanefforttorationalizethedesignofpipelines.Theimpactresponseofsteelpipelinessubjectedtoimpactloadinghasbeenstudiedinmanyarticles[1–8].Leisetal.[1]showedtheirworksofquantifyingtheeffectsofdentfeaturesonawinitiationandgrowthinhigh-pressurepipelines.Itwasreportedthatthefourfactorsthathaveastronginuenceontheseve-rityofthemechanicaldamageofthepipelinesaresoilsupport,linepressurelevel,linetensionorcompression,andthetype,magnitude,andtheorientationoftheimpactload.Thomasetal.[2]conductedaseriesofexperimen-taltestsonsimplysupportedtubesunderacentralload.Threedifferentmodesofdeformations,i.e.localdeformation,localandglobaldeformations,andstructuralcollapse,havebeenidentied.Correspondingauthor:JPKennyLtd,ThamesPlaza,ChertseyLane,StainesTW183DT,UK.email:ncs1018@Jonesetal.[3]successfullyconductedsevenseriesofimpacttestsoncoldworkedseamlessmildsteelpipes,whichhaddifferentspans,outsidediameters,andthicknesses.Thepipespecimensweresubjectedtoanimpactloadingatdifferentlocationswiththeimpactvelocitiesrangingupto14m/s.Atheoreticalrigid-perfectlyanalysisforpredictingthequasi-staticresponseofpipelinesthatarefullyclampedacrossaspanandsubjectedtoalateralimpactloadinghasbeendevelopedinreference[4].Thistheoreticalpredictionachievedagoodagree-mentwiththeexperimentalresultsinreference[3].JonesandBirch[5]presentedsomeexperimentaldata,whichwererecordedfromtheir54impacttestsonpressurizedandunpressurizedmildsteelpipes.Allthesepipesweresubjectedtoimpactload-ingfromarigidwedge-shapedindenter,whichhadaatimpactface.Moreover,thepipeswerefullyclampedacrossaspanandimpactedatthemid-andone-quarter-spanpositions.Theyrevealedtwomajorfailuremodesoccurringatthepipes,i.e.localfailureandglobalfailure.Morerecently,anexperimentalstudyonthefail-ureoffullyclampedsteelpipeswasreportedinProc.IMechEVol.220PartE:J.ProcessMechanicalEngineeringJPME97#IMechE2021194CSNgandWQShenreference[6].Atotalof226impacttestswereconductedonthediff...