MODELING AND ANALYSIS

ALTHOUGH FINITE ELEMENT CODES UTILIZING ELASTIC-PLASTIC-FRACTURING MODELS FOR CONCRETE STRUCTURAL ANALYSIS HAVE BEEN IN USE FOR NEARLY TWO DECADES, SEVERE STRUCTURAL DAMAGE INVOLVING SPALLING AND BREAKUP HAS REMAINED COMPUTATIONALLY INTRACTABLE. THIS PROPOSAL IS AIMED AT THE DEVELOPMENT OF A COMPUTATIONAL CAPABILITY FOR THE ANALYSIS OF REINFORCED CONCRETE STRUCTURES SUBJECTED TO SEVERE STRUCTURAL DAMAGE RESULTING FROM HIGH DYNAMIC LOADS AND DEFORMATION RATES. THIS INVOLVES THE MODELING OF REINFORCED CONCRETE IN THE POST CRITICAL RANGE WHICH INCLUDES CRACKING, SPALLING, CRUSHING AND STRUCTURAL SEPARATION AND THE DEVELOPMENT OF A COMPUTATIONAL PROCEDURE THAT COMBINES THE DEFORMATION-BASED FINITE ELEMENT METHOD AND THE RIGID-BODY KINEMATICS OF THE DISCRETE ELEMENT METHOD. IN THIS MANNER, ALL THREE INTERDEPENDENT RESPONSE REGIMES ARE TREATED, NAMELY, ELASTIC-PLASTIC DEFORMATIONS, SEVERE DAMAGE AND FINAL COLLAPSE. THE OBJECTIVES OF PHASE I EFFORT IS TO DEVELOP THE MODEL TO A LEVEL WHERE THE FEASIBILITY OF THE METHOD CAN BE ESTABLISHED. THE ULTIMATE OBJECTIVE OF THE PROPOSED RESEARCH IS TO DEVELOP A GENERAL ANALYSIS TOOL FOR REINFORCED CONCRETE STRUCTURES SUBJECTED TO CONVENTIONAL WEAPONS EFFECTS.