Study On The Fatigue Strength Of Floating Carrier Current Power Station

Fatigue damage is a major damaging in marine structures, so many national governments and research department development of structural fatigue damage for a number of ships and ocean engineering specification manuals and structural fatigue assessment documents. Many methods of structure fatigue strength are based on S-N curves and P-M theory. This method is the existence of such a large dispersion calculation results can not overcome such shortcomings. This report based on fracture mechanics, consider random load factors, assess the fatigue strength of a power plants’carrier structure, and establish a complete program of assessing marine structures’fatigue strength.First, fatigue and fracture mechanics theory of development of the theory are reviewed in this paper including home and aboard.Second, this paper describes the theory of fatigue fracture mechanics assessment and establishes a complete fatigue assessment method of marine structures based on fracture mechanics. The method takes into account random loading with constant amplitude fatigue loading difference, built a "semi-random time-domain method", which is aimed at controlling the amount calculated to achieve the time-domain analysis of structural fatigue.Third, the article focuses on the current power station’s environmental load in time domain spectrum, have introduced the irregular wave simulation, the generation of time-domain stress curve, current the equivalent processing flow, the conversion of turbine load. Finally, the load applied to the finite element model to analyze the structure of the stress response in time domain.Finally, current in a power plant, for example, from finite element modeling, environmental load application, select the sea states, crack growth model calculation, to results analysis and given current of a power plant the final fatigue life, showing a complete calculation program and calculation details.This paper built a computing fatigue strength of current power station basing on fracture theory, and hopping the method in this paper can help other researchers in the future.