简介：Inmarineengineering,thestrengthofasubmarinesedimentisanindispensableparameterforassessmentofconstruction.Inthisstudy,afree-fallconepenetratornamedIPenwasdevelopedtorealizearapidandefficientmeasurementofsedimentstrength.Theequipmentischaracterizedbymodulardesignandself-containeddataacquisition.Itisequippedwithanaccelerationsensor,awaterpressuresensor,andapiezoconepenetrationtest(CPTu)probe.Itisdesignedtobereleasedfromnearseabedsurfacewithareleaserandthenfallfreelytoprovideahigherpenetrationvelocity.Itsmaximumworkingdepthisapproximately2500mandmaximumpenetrationdepthisapproximately3m.Toderivethecorrelationbetweenpenetrationresistanceandsedimentstrength,acalibratorwasdevisedtodeterminethepenetration-ratefactor.Inaddition,thefactorapplicabletoinsitutestpointswasdeterminedinlaboratoryexperiments.InJune2016,theIPenwastestedinsituintheSouthYellowSea,China,duringasharedvoyagefundedbytheNationalScienceFoundation.Meanwhile,undisturbedcolumnsampleswerecollectedforlaboratorytests.Basedontheinsitutestresults,itwasdemonstratedthattheIPencouldaccuratelyrecordtheworkingstatesofvarioussensorsduringthefreelyfallingcourse.IPentestresultsreliablyreflectedthesedimentstrengthatallthetestingpointswhencomparedwithlaboratorycalibrationtests,insituvanetestsandpenetrationtests,laboratorypenetrationtests,andunconsolidatedandundrainedtriaxialcompressiontests.