简介：AnewcentrifugebasedmethodfordeterminingtheresponseofcontinuousburiedpipetoPGDispresented.ThephysicalcharacteristicsoftheRPI's100g-tongeotechnicalcentrifugeandthecurrentlifelineexperimentsplit-boxaredescribed:Thesplit-boxcontainsthemodelpipelineandsurroundingsoilandismanufacturedsuchthathalfcanbeoffset,inflight,simulatingPGD.Inaddition,governingsimilituderelationswhichallowonetodeterminethephysicalcharacteristics,(diameter,wallthicknessandmaterialmodulusofelasticity)ofthemodelpipelinearepresented.Finally,recordedstrainsinducedintwoburiedpipeswithprototypediametersof0.63mand0.95m(24and36inch)subjectto0.6and2.0meters(2and6feet)offullscalefaultoffsetsandpresentedandcomparedtocorrespondingFEresults.

简介：Thisstudyconsidersthetorsionalvibrationofapipepileinatransverselyisotropicsaturatedsoillayer.BasedonBiot’sporoelastictheoryandtheconstitutiverelationsofthetransverselyisotropicmedium,thedynamicgoverningequationsoftheouterandinnertransverselyisotropicsaturatedsoillayersarederived.TheLaplacetransformisusedtosolvethegoverningequationsoftheouterandinnersoillayers.Thedynamictorsionalresponseofthepipepileinthefrequencydomainisderivedutilizing1Delastictheoryandthecontinuousconditionsattheinterfacesbetweenthepipepileandthesoils.ThetimedomainsolutionisobtainedbyFourierinversetransform.Aparametricstudyisconductedtodemonstratetheinfluenceoftheanisotropiesoftheouterandinnersoilonthetorsionaldynamicresponseofthepipepile.

简介：Thepropagationofstresswavesinalarge-diameterpipepileforlowstraindynamictestingcannotbeexplainedproperlybytraditional1Dwavetheories.Anewcomputationalmodelisestablishedtoobtainawaveequationthatcandescribethedynamicresponseofalarge-diameterthin-walledpipepiletoatransientpointloadduringalowstrainintegritytest.Ananalyticalsolutioninthetimedomainisdeducedusingtheseparationofvariablesandvariationofconstantmethods.Thevalidityofthisnewsolutionisverifiedbyanexistinganalyticalsolutionunderfreeboundaryconditions.Theresultsofthistimedomainsolutionarealsocomparedwiththeresultsofafrequencydomainsolutionandfieldtestdata.Thecomparisonsindicatethatthenewsolutionagreeswellwiththeresultsofprevioussolutions.Parametricstudiesusingthenewsolutionwithreferencetoacasestudyarealsocarriedout.Theresultsshowthatthemodenumberaffectstheaccuracyofthedynamicresponse.Amodenumbergreaterthan10isrequiredtoenablethecalculateddynamicresponsestobeindependentofthemodenumber.Thedynamicresponseisalsogreatlyaffectedbysoilproperties.Thelargerthesideresistance,thesmallerthedisplacementresponseandthesmallerthereflectedvelocitywavecrest.Thedisplacementincreasesasthestresswavespropagatealongthepilewhenthepileshaftisfree.Theincidentwavesofdisplacementandvelocityresponsesofthepilearenotthesameamongdifferentpointsinthecircumferentialdirectiononthepiletop.However,thearrivaltimeandpeakvalueofthepiletipreflectedwavesarealmostthesameamongdifferentpointsonthepiletop.