Numerical analysis of projectile penetration and perforation of plain and fiber reinforced concrete slabs

Abstract

Summary The research presented in this paper deals with the numerical analysis of projectile impact on regular strength concrete (RSC), high‐strength concrete (HSC), and engineered cementitious composites (ECC) using the Lattice Discrete Particle Model (LDPM). The LDPM is chosen in this study as it naturally captures the failure mechanisms at the length scale of coarse aggregate of concrete, and its capabilities include the accurate depiction of both intrinsic and apparent rate effects in concrete, as well as fiber reinforcement effects. The model is used to predict the experimental impact response performed by four independent testing laboratories, and for each data set the model parameters are calibrated and validated using a combination of uniaxial compression, triaxial compression, uniaxial strain compression, and dogbone tests. In the first study, perforation experiments on RSC and HSC for varied impact velocities are carried out, and the exit velocity is compared with the available experimental data. The second study focuses on ECC, where multiple impact of steel and plastic fiber reinforced concrete panels are explored. A third investigation is performed on four RSC panels with varied thicknesses and subjected to the same impact velocity. In this instance, the model is used to predict the penetration depths for the different cases. Finally, in the last study, the response of large‐thickness infinite panels of sizes ranging from 300 mm to 700 mm under projectile impact is considered. Copyright © 2016 John Wiley & Sons, Ltd.

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