Calculation of Total Longitudinal Bending Stress of Damaged Hull Based on a Modified Equivalent Beam Method

Abstract

This paper proposes a modified equivalent straight beam method to calculate the total longitudinal strength of a damaged hull. Firstly, the average stress is obtained by the method of original equivalent beam, and then the stress concentration coefficient of sharp corner rectangular fracture is analysed. The stress concentration coefficient of the fracture is divided into the plate stress concentration coefficient and stiffeners coefficient, and a simplified algorithm is put forward according to their progressive law. In addition, considering the nonlinearity of the material, the correction formula of elastic stress concentration coefficient is fitted. Finally, the calculation results based on modified equivalent beam methods make the damage hull strength check more realistic and reliable.