SLIPPAGE OF ARAMID FABRICS IN BLAST AND BALLISTIC IMPACT TESTS. FINITE ELEMENT MODELLING METHODS AND CONSEQUENCES IN BALLISTIC RESISTANCE

The sliding of samples in blast and ballistic impact tests is a frequently reported phenomenon. The inward response of materials to out of plane impulsive loads results in reaction forces from the boundaries that exceed, temporarily, the clamping forces. In this work, Aramid fabrics are subjected to blast loading tests for characterizing the magnitude of their slipped boundaries from a circular clamping device. A Finite Element model describing a mesoscale Aramid Fabric with conditional frictional sliding boundaries subjected to blast loads is developed based on the experimental results. A second model configured for ballistic impact is developed in order to quantify the influence of slippage in the ballistic performance. The results reveal that more energy is absorbed when slippage is considered.