简介：Astheoffshoreindustriesmovefromshallowtodeepwatersinexcessof1000m,therehasbeenrapiddevelopmentofoceanengineeringpractices.Innovationsintheoreticalandappliedmechanicshavebeenessentialinthisshiftandinunderpinningtheexploitationofoffshoreoilandgasandrenewableenergyresourcesworldwide.Understandingandpredictingphysicalmechanismsofstructure-soilinteractionsarevitalforthestabilityandsafetyofoffshoreengineeringstructures.Accordingly,inthisspecialissueofTheoretical&AppliedMechanicsLetters(TAML),eight

简介：Anumericalmethod,theso-calledmultiplemonopole(MMoP)method,basedonthegeneralizedmultipoletechnique(GMT)isproposedtocalculatethebandstructuresofin-planewavesintwo-dimensionalphononiccrystals,whicharecomposedofarbitrarilyshapedcylindersembeddedinasolidhostmedium.Tofindtheeigenvalues(eigenfrequencies)oftheproblem,besidesthesourcesusedtoexpandthewavefields,anextramonopolesourceisintroducedwhichactsastheexternalexcitation.Byvaryingtheexcitationfrequency,theeigenvaluescanbelocalizedastheextremepointsofanappropriatelychosenfunction.BysweepingthefrequencyrangeofinterestandtheboundaryoftheirreduciblefirstBrillouinzone(FBZ),thebandstructurescanbeobtained.Sometypicalnumericalexampleswithdifferentacousticimpedanceratiosandwithinclusionsofvariousshapesarepresentedtovalidatetheproposedmethod.