Performance Analysis of Multi-Layer Concrete Structures for Security Centers Using Dynamic Simulations
Authors: Hatami Dezdarani Vahid , Pour Mohammadi Mohammad Hossein 
Published: October 2024

This paper explores the performance analysis of multi-layer concrete structures specifically designed for security centers and high-risk governmental facilities. These structures face unique challenges due to the nature of the threats they are exposed to, such as explosions, seismic activities, and impact from high-velocity objects. To address these challenges, multi-layered concrete systems offer a promising solution by combining different materials in layers to maximize resistance and energy absorption [1]. In this study, we focus on understanding how the layered design impacts the overall structural integrity and durability under dynamic loading conditions. Security centers are critical infrastructures that require advanced structural designs to ensure the safety of personnel, assets, and sensitive information. Traditional monolithic concrete structures, while robust, often fail to provide adequate protection under extreme forces. Multi-layer concrete structures, on the other hand, offer improved performance by distributing stresses more effectively and limiting crack propagation [2]. This study employs advanced finite element analysis (FEA) simulations, using tools such as ANSYS and Abaqus, to evaluate the performance of these systems under various dynamic load scenarios, including blast loads, seismic events, and high-velocity impacts. The multi-layered systems studied in this paper consist of a combination of regular concrete, highstrength concrete (HSC), and fiber-reinforced concrete (FRC). Each layer plays a distinct role in enhancing the overall structural resilience: the outer layer absorbs the initial impact and disperses the energy across the structure, while the inner layers provide strength and stability, minimizing deformation and damage. The FRC layer, in particular, significantly enhances tensile strength, mitigating the risk of sudden structural failure. Our simulations were designed to model realistic scenarios that these structures would likely encounter. For example, in the blast load analysis, an explosion was simulated at varying distances from the structure to evaluate how well the multi-layer system could absorb and dissipate the shockwave. The results showed that multi-layer systems significantly outperformed traditional concrete structures in terms of energy absorption and crack mitigation. The outermost layer bore the brunt of the blast, while inner layers remained largely intact, protecting the core structure. This layered approach drastically reduced stress concentrations, limiting the severity and extent of crack propagation. In the seismic performance simulations, multi-layer systems demonstrated enhanced resilience by reducing peak displacements and distributing seismic forces more uniformly. This allowed the structure to maintain its integrity longer than its monolithic counterparts, which typically failed earlier under the same conditions. The seismic response of these multi-layered structures was also more controlled, with less damage occurring in critical areas such as joints and connections. By analyzing the time-history response and frequency domain behavior, we were able to observe the benefits of the layered system in mitigating resonance effects and reducing overall structural vibrations during earthquakes. Another critical aspect examined in this research is the impact resistance of the multi-layer systems. Simulations modeled high-velocity impacts, such as projectiles or debris from explosions, hitting the structure. The FRC layers proved particularly effective in preventing penetration and absorbing the kinetic energy of the impact, limiting damage to the inner layers. This finding is crucial for designing structures intended to withstand targeted attacks or accidental collisions.