简介：Vacuumloadinghasbeenexaminedasawayofpreparinguniformlyconsolidatedsoftclaysamples.Thefacilityandloadingprocedurearedescribedinthispaper.Ananalyticalsolutiontothethreedimensionalconsolidationequationisderivedforestimatingthedegreeofconsolidationofthesoilsamplewithvacuumloading.Thegivenexampleshowsthatthepredicteddegreeofconsolidationofasoftclaybulkwithvacuumloadingisclosetothatmeasuredintheconsolidationprocess.

简介：Theresultsofundrainedcyclictriaxialtestsonthreetypesofclaysarecollectedandarelationshipamongtheaccumulatedstrain,theinitialstressstate,cyclicstressinthesoil,aswellasthenumberofcyclesisestablishedbasedontheexperimentaldata.Withthisrelationship,aprocedureisproposedforsubsidenceandstabilityanalysisonsoftclayundertheactionofcyclicloads.

简介：Thedegradationstrengthofsoilsundercyclicloadingisstudiedandamethodfordeter-miningthecyclicdegradationstrengthwithcyclictriaxialtestsisgiveninthepaper.Furthermore,adum-mystaticmethodforestimatingtheundrainedbearingcapacityforoffshoresoftfoundationunderwaveloadsisdeveloped.Itcanconsidertheeffectofthedifferenceofcyclicstressfordifferentpartsofthefoun-dationonboththedegradationstrengthofthefoundationsoilandthebearingcapacitysothattheesti-matedresultcanbetterreflecttherealconditionoffoundationundercyclicloading.Themethodcanbeap-pliedtoplaneandspaceproblem.

简介：MuchattentionshouldbepaidtoalargeFPSOmooredpermanentlyinanoilfieldwithwaterdepthofonlyabout20m,sinceshallowwatereffectsonthehydrodynamicsmaybringaboutcollisionanddamage.A160kDWTFPSOwithapermanentsoftyokemooringsystemisinvestigatedwithvariousshallowwaterdepthsandfocusesarethelowfrequencysurgemotionandmooringload.ComputationfortheFPSOsystemismadebasedonlinear3-Dpotentialfluidtheoryandtime-domainnumericalsimulationmethod.CorrespondingmodeltestiscarriedoutintheoceanengineeringbasinofShanghaiJiaoTongUniversity.Itisshownthat,inthesurgenaturalperiod,lowfrequencysurgemotionandmooringforceincreaseremarkablywiththedecreaseofwaterdepth.Especially,thesmallertheratioofwaterdepthanddraughtis,thequickertheincreaseis.Theshallowwatereffectsshouldbetakenintoaccountcarefullyfordeterminingthedesignloadofasinglepointmooringsystem.

简介：ExplosionforthetreatmentofunderwatersoftfoundationisatechniquenewlydevelopedinChina.ThispaperdescribestheapplicationofthemethodofexplosiontounderwatersoftfoundationtreatmentoftheGreat-WestDyke,LianyungangPort,includingthetechnicalcharacteristicsandtheeffect,selectionofexplosionparameters,workmanshipofconstruction,requirementsofqualityandinspection,andthelike.

简介：Stiffnessdegradationwilloccurduetothegenerationofaccumulatedporepressureinsaturatedsoftclaysundercyclicloading.Thesoilstatic-dynamicmulti-purposetriaxialandtorsionalshearapparatusinDalianUniversityofTechnologywasemployedtoperformdifferenttypesoftestonthesaturatedsoftmarineclayintheYangtzeEstuary.Undisturbedsamplesoftheclayweresubjectedtoundrainedcyclicverticalandtorsionalcouplingshearandcyclictorsionalshearafterthree-directionalanisotropicconsolidationwithdifferentinitialconsolidationparameters.Investigatedweretheeffectsoftheinitialorientationangleofthemajorprincipalstress,initialratioofdeviatoricstress,initialcoefficientofintermediateprincipalstressandcontinuousrotationofprincipalstressaxesonthestiffnessdegradation.Itisfoundthatthedegradationindexdecreases(ordegradationdegreeincreases)significantlywithincreasinginitialorientationangleofthemajorprincipalstressandinitialratioofdeviatoricstress.Comparedwiththeeffectsoftheinitialorientationangleofthemajorprincipalstressandinitialratioofdeviatoricstress,theeffectofinitialcoefficientofintermediateprincipalstressislessevidentandthistrendismoreclearlyreflectedbytheresultsofthecyclictorsionalshearteststhanthoseofthecycliccouplingsheartests.Atthesamecyclenumber,thedegradationindexobtainedfromthecyclictorsionalsheartestishigherthanthatfromthecycliccouplingsheartest.Themainreasonisthatthecontinuousrotationinprincipalstressdirectionsduringcycliccouplingsheardamagestheoriginalstructureofthesoilmorethanthecyclictorsionalsheardoes.Basedonaseriesofexperiments,amathematicalmodelforstiffnessdegradationisproposedandtherelevantparametersaredetermined.