Theory of the Ship and Construction Mechanics
DOI: http://www.dx.doi.org/10.24866/2227-6858/2020-1-6
Matokhin G., Molokov K., Novikov V., German A.
GENNADY MATOKHIN, Doctor of Engineering Sciences, Professor, e-mail: matohin@bk.ru
KONSTANTIN MOLOKOV, Candidate of Engineering Sciences, Associate Professor,
ScopusID: 57197836777, e-mail: spektrum011277@gmail.com
Department of Welding, School of Engineering
VALERY NOVIKOV, Candidate of Engineering Sciences, Associate Professor,
Scopus ID: 5641710410, e-mail: Leka1551@rambler.ru
ANDREY GERMAN, Associate Professor, ORCID: 0000-0002-9530-5258,
Scopus ID: 56417290300, e-mail: german.ap@dvfu.ru
Department of Shipbuilding and Ocean Engineering, School of Engineering
Far Eastern Federal University
8 Sukhanova St., Vladivostok, Russia, 690091
Mathematical model for determining the operational life
of ship structures
Abstract: The operational resource of the hull structure of a marine vessel depends on many technical and economic factors. Microdefects of steel, which under cyclic loads lead to the occurrence of structural damage to the metal, low-cycle or high-cycle fatigue and the propagation of cracks in the hull braces, especially in welded joints, have a great influence on the capacity and durability. Estimation methods for calculation of residual life involve the use of a hypothetical rate of microcrack development, which is unknown (in many cases) and cannot be always measured with any experimental degree of accuracy. The proposed in this paper author’s method of determination its initial velocity is based on an analytical approach which uses the well known calculation or evaluation value of the endurance limit of ferrite-pearlite steel and considering in order to solve problems of the joint for the first two parts of the kinetic diagram of fatigue fracture. The developed mathematical model for carrying out the proposed method allows us to use an approximate engineering approach to determine the residual fatigue life of ship structures and its welded joints.
Keywords: structural resource, ferrite-pearlite steel, microcrack, macrocrack, fracture kinetics, Paris equation, endurance limit.
See the reference in English at the end of the article