# Frontiers of Structural and Civil Engineering

 Front. Struct. Civ. Eng.    2019, Vol. 13 Issue (5) : 1120-1137     https://doi.org/10.1007/s11709-019-0540-8
 RESEARCH ARTICLE
An investigation of ballistic response of reinforced and sandwich concrete panels using computational techniques
Sonny Astani Department of Civil and Environmental Engineering, University of Southern California, Los Angeles, CA 90007, USA
 Download: PDF(2600 KB)   HTML Export: BibTeX | EndNote | Reference Manager | ProCite | RefWorks
 Abstract Structural performance of nuclear containment structures and power plant facilities is of critical importance for public safety. The performance of concrete in a high-speed hard projectile impact is a complex problem due to a combination of multiple failure modes including brittle tensile fracture, crushing, and spalling. In this study, reinforced concrete (RC) and steel-concrete-steel sandwich (SCSS) panels are investigated under high-speed hard projectile impact. Two modeling techniques, smoothed particle hydrodynamics (SPH) and conventional finite element (FE) analysis with element erosion are used. Penetration depth and global deformation are compared between doubly RC and SCSS panels in order to identify the advantages of the presence of steel plates over the reinforcement layers. A parametric analysis of the front and rear plate thicknesses of the SCSS configuration showed that the SCSS panel with a thick front plate has the best performance in controlling the hard projectile. While a thick rear plate is effective in the case of a large and soft projectile as the plate reduces the rear deformation. The effects of the impact angle and impact velocity are also considered. It was observed that the impact angle for the flat nose missile is critical and the front steel plate is effective in minimizing penetration depth. Corresponding Authors: Bora GENCTURK Just Accepted Date: 24 May 2019   Online First Date: 26 June 2019    Issue Date: 11 September 2019
 Cite this article: Mohammad HANIFEHZADEH,Bora GENCTURK. An investigation of ballistic response of reinforced and sandwich concrete panels using computational techniques[J]. Front. Struct. Civ. Eng., 2019, 13(5): 1120-1137. URL: http://journal.hep.com.cn/fsce/EN/10.1007/s11709-019-0540-8 http://journal.hep.com.cn/fsce/EN/Y2019/V13/I5/1120
 Fig.1  Cross-sectional view of the panels (a) SCSS; (b) RC Tab.1  Geometry and material properties of the experiment [30] Tab.2  Summary of FE used in modeling Fig.2  Meshing of the SCSS configuration. The concrete block has the same mesh density in the RC configuration Tab.3  The parameters of the CDP model [29] Fig.3  Uniaxial stress-strain behavior for 23 MPa concrete in (a) compression; (b) tension Tab.4  Concrete properties Tab.5  Material properties of steel plates and rebar Fig.4  Stress-strain curve for steel (a) reinforcement; (b) plate Tab.6  Results of mesh sensitivity study Fig.5  An example plot of artificial strain energy (ASE) to internal energy (IE) ratio Fig.6  Conventional FE simulation results for (a) side view; (b) isometric view. Damage varies between zero and unity for no and complete damage, respectively Fig.7  Reaction force time history Fig.8  SPH model (a) improved boundary conditions; (b) compressive damage. In part (b), damage varies between zero and unity for no and complete damage, respectively Tab.7  Comparison of experimental results from penetration tests on the SCSS panel [30] with the experimental data Fig.9  Equivalent plastic strain, PEEQ, at (a) 5 ms; (b) 15 ms; (c) 30 ms Tab.8  Input parameters for empirical models and unit conversion factors Fig.10  Comparison between the empirical equations and the conventional FE model Tab.9  Parametric analysis of the steel plate thicknesses Fig.11  Rear plate displacement at the center Fig.12  Velocity of the projectile Fig.13  Penetration depth time history Tab.10  Parametric analysis of the kinetic energy of the projectile Fig.14  Compressive damage and penetration depth for the projectile with (a) 200 m/s; (b) 600 m/s impact velocity. Damage varies between zero and unity for no and complete damage, respectively Fig.15  Residual velocity of the projectile versus different initial velocities Tab.11  Parametric analysis of the impact angle Fig.16  Compressive damage at different time steps for Case 5 with 0.4 ms time step. Damage varies between zero and unity for no and complete damage, respectively Fig.17  (a) Tensile; (b) Compressive damage for Case 5 at t = 16 ms. Damage varies between zero and unity for no and complete damage, respectively Fig.18  von Misses stress (MPa) in the front plate for Case 6 Fig.19  (a) Penetration depth, (b) rear deformation for different impact angles Fig.20  (a) Tensile; (b) compressive damage at v= 0 m/s for v0 = 300 m/s. Damage varies between zero and unity for no and complete damage, respectively Fig.21  Rear plate displacement at the center Tab.12  Parametric analysis of the impact angle