Research on damage viscoelastic dynamic constitutive model of granite

DynamicmechanicalpropertiesofgraniteweretestedbyasplitHopkinsonpressurebarsystemwithconstantstrainrate.Theinitialloadingstageofstress-straincurveofgraniteislinearelasticity, andtherockmaterialhasasignificantplasticdeformationafteryielding.Yieldstrength,peakstrength andelasticmodulusareallratedependent.Basedondynamicmechanicalpropertyofgranite,theconstitutiveofZhu-Wang-Tangmodelwassimplifiedto apply on granite,and with consideration of the effectofdamageonthedynamicstrengthofgraniteunderimpactload.Theexperimentaldatawerefitted totheproposedmodel.Thefittedstress-straincurvesatdifferentstrainratesareingoodagreementwith theexperimentalones.Thisdemonstratesthattheproposeddynamicconstitutivemodelinthispapercan accuratelydescribethedynamicmechanicalpropertiesofgraniteundertheimpactload.