EXPERIMENTAL EVALUATION OF LOW-PASS SHOCK ISOLATION PERFORMANCE OF ELASTOMERS USING FREQUENCY-BASED KOLSKY BAR ANALYSES

Abstract

ELASTOMERIC MATERIALS ARE USED AS SHOCK ISOLATION MATERIALS IN A VARIETY OF ENVIRONMENTS TO DAMPEN VIBRATIONS AND/OR ABSORB ENERGY FROM EXTERNAL IMPACT FOR MINIMIZING ENERGY TRANSFER BETWEEN TWO OBJECTS OR BODIES. SOME APPLICATIONS REQUIRE THE SHOCK ISOLATION MATERIALS TO BEHAVE AS A LOW-PASS MECHANICAL FILTER TO MITIGATE THE SHOCK/IMPACT AT HIGH FREQUENCIES BUT TRANSMIT THE ENERGY AT LOW FREQUENCIES WITH MINIMAL ATTENUATION. IN ORDER TO FULFILL THIS REQUIREMENT, A SHOCK ISOLATION MATERIAL NEEDS TO BE CAREFULLY EVALUATED AND SELECTED WITH PROPER EXPERIMENTAL DESIGN, PROCEDURES, AND ANALYSES. IN THIS STUDY, A KOLSKY BAR WAS MODIFIED WITH PRE-COMPRESSION (UP TO 15.5 KN) AND CONFINEMENT CAPABILITIES TO EVALUATE LOW-PASS SHOCK ISOLATION PERFORMANCE IN TERMS OF ACCELERATION ATTENUATION THROUGH A VARIETY OF ELASTOMERS. THE EFFECTS OF PRELOAD AND SPECIMEN GEOMETRY ON THE LOW-PASS SHOCK ISOLATION RESPONSE WERE ALSO INVESTIGATED.