Plainconcreteisregardedasatwo-phasematerialcomprisingrandomlydistributedaggregatesandmortarmatrix.Aseriesofthree-pointbendingconcretebeamswithsymmetricorasymmetricdoublenotchesaremodeledusingthemodifiedrandomaggregategenerationandpackingalgorithm.Thecohesivezonemodelisusedasthefracturecriterionandthecohesiveelementsareinsertedintoboththemortarmatrixandtheaggregate-mortarinterfacesaspotentialmicro-crackingzones.Thedeadandalivecrackphenomenaarestudiedexperimentallyandnumerically;andtheinfluencesofnotchlocation,aggregatedistributionandgradationonfracturearenumericallyevaluated.Someimportantconclusionsaregiven.