Forecasting Ultimate Strength of Designed Thin-Walled VLCC Class Structures Based on Imperfection and Pressure Severities: Benchmarking and Developing Empirical Formula

Aulia Widsay Salsabila Nisa1

Ristiyanto Adiputra2,Email

Aditya Rio Prabowo1,Email

Do Kyun Kim3

Heru Sukanto1

Yogie Muhammad Lutfi1,4

Muhammad Hanif Imaduddin1,4

1Department of Mechanical Engineering, Universitas Sebelas Maret, Surakarta 57126, Indonesia.
2Research Center for Hydrodynamics Technology, National Research and Innovation Agency (BRIN), Surabaya 60117, Indonesia.
3Department of Naval Architecture and Ocean Engineering, Seoul National University, Seoul 08826, South Korea.
4Laboratory of Design and Computational Mechanics, Faculty of Engineering, Universitas Sebelas Maret, Surakarta 57126, Indonesia.

Abstract

The increasing number of accidents involving Very Large Crude Carriers (VLCCs) has heightened concerns regarding ship safety and structural integrity. Stiffened panels have emerged as a crucial element in reinforcing ship structures effectively without significantly adding weight. Reliability analysis has been extensively conducted to evaluate the strength of stiffened panels with various parameters. However, considering lateral pressure parameters on structural strength has not received adequate attention in reliability analysis and has only been presented as single values. This necessitates a more profound investigation to understand the distributional effects of lateral pressure on initial deflection enhancement and the reduction in ultimate strength values. To address this gap, the current study introduced modifications to the parameters, including slenderness ratio, span/bay ratio, yield strength, initial imperfection, and pressure. A total of 216 data points were obtained through numerical Finite Element Method (FEM) simulations using ABAQUS. The obtained ultimate strength values were statistically analyzed using a T-test to explore correlations among the parameters. Subsequently, a regression analysis was conducted to formulate an empirical formula. The resulting empirical formula demonstrated remarkable accuracy, with a Mean Absolute Percentage Error (MAPE) of merely 0.801%, when compared to the FEM numerical results, thus substantiating its validity as an effective and efficient solution for predicting ultimate strength values influenced by pressure.