دانلود رایگان مقاله انگلیسی مدل سازی عددی از تاثیر با سرعت بالا به پنل بتن مسلح - الزویر 2018

Abstract

A numerical simulation of a high-velocity impact of reinforced concrete structures is a complex problem for which robust numerical models are required to predict the behavior of the experimental tests. This paper presents the implementation of a numerical model to predict the impact behavior of a reinforced concrete panel penetrated by a rigid ogive-nosed steel projectile. The concrete panel has dimensions of 675 mm
675 mm
200 mm, and is meshed using 8-node hexahedron solid elements. The behavior of the concrete panel is modeled using a Johnson-Holmquist damage model incorporating both the damage and residual material strength. The steel projectile has a small mass and a length of 152 mm, and is modeled as a rigid element. Damage and pressure contours are applied, and the kinetic and internal energies of the concrete and projectile are evaluated. We also evaluate the velocity at different points of the steel projectile and the concrete panel under an impact velocity of 540 m/s.

Conclusion

A numerical simulation of the penetration of a highvelocity impact through a reinforced concrete panel was simulated in this work. Because of the neglected effects of the steel reinforcement on the impact resistance of reinforced concrete structures, the simulated target was considered as plain concrete. The concrete material was modeled using the Johnson–Holmquist damage model (JH-2), and the steel ogive-nosed projectile used was simulated as a rigid body with a mass of 0.386 kg assigned at a reference point. The variations in velocity at different points of the projectile and concrete panel, as well as the damage and pressure, were evaluated. Analyses of the internal energy of the concrete panel and the kinetic energy of the steel projectile were also conducted. The kinetic energy of the projectile was shown to decrease, and once the projectile penetrates into the concrete panel, the panel tended to absorb the energy of the projectile, and thus enhancing stability of the projectile. It was found that the results of the kinetic and internal energies fit the results of the damage and pressure in terms of the penetration time of the projectile into the concrete panel as well as the impact behavior. It was shown that the Johnson–Holmquist damage model (JH-2) can be utilized to describe the impact behavior of a plain concrete panel. Future work may focus on an analysis of the influence of the spatial and time discretizations, and the uncertain input parameters on the results of the impact modeling.