PSI - Issue 81

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ScienceDirect

Procedia Structural Integrity 81 (2026) 58–65

© 2026 The Authors. Copy from the contract: Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of DMDP 2025 organizers Keywords: Underwater Explosion; Sandwich Panel; Finite Element Analysis; Shock Wave – Structure Interaction; Constant Shock Factor 1. Introduction As the construction of naval vessels increases, threats arising from internal structural loads, accidental loading conditions, and underwater weapons have become increasingly complex to mitigate. Previous studies have addressed these issues in the context of naval and marine structures, including the works of Fajri et al. (2022), Fuadi et al. (2025), Prabowo et al. (2016, 2018, 2023, 2025), Malsyage et al. (2025), and Zhao et al. (2025). During maritime operations, naval vessels are particularly vulnerable to anti-ship weapons, with near-field torpedo detonations among the most destructive threats. Exposure to underwater explosions (UNDEX) can induce local damage, hull failure, and even compromise overall structural integrity, as reported by Zhang et al. (2015). UNDEX generates high-pressure shock waves that propagate through the surrounding water, characterized by an abrupt pressure rise followed by exponential decay, making them one of the most severe loading conditions acting on marine structures (Marchesi et Abstract Underwater Explosions (UNDEX) produce high-pressure shock waves that can disrupt the ship's structural integrity and trigger catastrophic failure. One innovative approach to improving resistance to shock loads is the use of sandwich panels, which utilize specific core configurations to absorb energy and limit deformation. This study investigates the mechanical response of sandwich panels with four cellular core configurations — S-core, U-core, X-core, and Y-core — to UNDEX shock loads under a constant Shock Factor (SF) scenario. Simulations were conducted using a finite element-based acoustic-structural analysis method to model shock wave-structure interactions in the fluid domain. The results show that, with the same SF, the performance of the sandwich panel differs slightly, along with the differences in Trinitrotoluene (TNT) mass and stand-off distance. VIII International Conference “In - service Damage of Materials: Diagnostics and Prediction“ (DMDP 2025) Numerical investigation of cellular core sandwich panels subjected to UNDEX: The constant shock factor case Anandito Adam Pratama a , Teguh Muttaqie b , Aditya Rio Prabowo a,* , Quang Thang Do c , Haris Nubli d , Hermes Carvalho e,f a Department of Mechanical Engineering, Universitas Sebelas Maret, Surakarta, Indonesia b Research Center for Hydrodynamics Technology, National Research and Innovation Agency (BRIN), Surabaya, Indonesia c Department of Naval Architecture and Ocean Engineering, Nha Trang University, Nha Trang, Viet Nam d School of Engineering, University of Surrey, Guildford, United Kingdom e Department of Structural Engineering, Federal University of Minas Gerais, Belo Horizonte, Brazil f Department of Structural Engineering and Geotechnical, University of São Paulo, São Paulo, Brazil

* Corresponding author. Tel.: +62-271-163-632; fax: +62-271-163-632. E-mail address: aditya@ft.uns.ac.id

2452-3216 © 2026 The Authors. Copy from the contract: Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of DMDP 2025 organizers 10.1016/j.prostr.2026.03.011