CONCRETE PENETRATION BY ERODING PROJECTILES - EXPERIMENTS AND ANALYSIS

Spherical-nose copper and tantalum rods with aspect ratios between 4.0 and 14.6 were gun launched against 98-cm-diameter and 91-cm-long conc rete and simulant reinforced-concrete targets with velocities ranging from 0.15 cm/mu s to 0.19 cm/mu s. Targets were instrumented with a se quence of break gauges that provided valuable data for characterizing the penetration process. Target-hole profiles and projectile residual masses were measured and reported. Analysis of the penetration perform ance of projectiles was performed within the framework of the modified hydrodynamic theory of pen'etration. Based on the results of these ca lculations, the penetration efficiencies of the copper and the tantalu m projectiles were compared as functions of impact velocities. Analysi s of the penetration resistance of the simulant reinforced-concrete ta rgets was based on treating the targets as ''composites,'' comprised o f layers of concrete proper and reinforcing steel; the results of thes e calculations were compared with the experimental data. Using this th eory, the penetration resistance of a concrete/steel/concrete ''compos ite'' was investigated as a function of the following parameters: thic kness of the surface layer of the concrete, thickness of the steel rei nforcement, and impact velocity.