ENERGY ABSORPTION OF ALUMINUM PANELS SUBJECTED TO GELATIN PROJECTILE IMPACT

Abstract

THE MOTIVATION OF THIS PAPER IS THE INTERESTS OF INVESTIGATING THE RESPONSE OF STRUCTURES WHEN SUBJECTED TO SOFT IMPACT LOADINGS. TRADITIONAL RESEARCHES HAVE TROUBLES WHEN FACING THE CHALLENGE OF COMPLEX COUPLING BETWEEN TARGET’S DYNAMIC RESPONSE AND THE LOADING PROCESS. THE PRESENT STUDY USED DIGITAL IMAGE CORRELATION (DIC) METHOD TO OBTAIN THE REAL-TIME 3D DEFORMATIONS OF TARGETS LOADED BY TRAJECTORY GELATIN PROJECTILES. CAREFULLY CALIBRATION AND SYNCHRONIZATION WERE CONDUCTED TO ENSURE THE ACCURACY OF THE TESTS. IN ORDER TO ESTIMATE THE CORRELATION CALCULATIONS, EVALUATIONS BETWEEN THE DIC RESULTS AND POST-TEST RESULTS WERE MADE. THE PLASTIC FLOW OF THE PARTICLES ON THE PANEL WERE OBSERVED, AND THE IN-PLANE DISPLACEMENTS WERE NEGLIGIBLE COMPARED TO OUT-OF-PLANE DEFLECTIONS. WITH THE HELP OF TIME-DEPENDENT PROFILES OF TARGET PANELS, THEIR ENERGY ABSORPTION PROPERTIES WERE THEORETICALLY ANALYZED, INCLUDING THE EXCHANGE OF KINETIC ENERGY AND PLASTIC WORK. THE RESULTS SHOWED THAT WHEN THE IMPACT LOADINGS WERE INCREASED, THE PLASTIC WORK GENERATED BY RADIAL MEMBRANE FORCE BECAME THE MAJOR SOURCE OF ENERGY DISSIPATION. THE TRANSVERSE MOVEMENTS OCCUPIED MORE KINETIC ENERGIES THAN ROTATORY MOMENTS. THE INFLUENCE OF ELASTIC DEFORMATIONS CANNOT BE IGNORED IN THE SOFT IMPACT EVENTS, THEREFORE MORE PRECISE MODELS ARE REQUIRED IN THE FUTURE TO DESCRIBE THE PANELS’ STATE OF STRESS.