Abstrakt

Analysis of the Fuselage Structure for Multi Site Damage

Karthik N, Dr. C Anil Kumar

The current study includes a panel which represents the fuselage splice joint. The fuselage splice joint is a location where it experiences the uniform stress field at many rivet locations in a row. The probability of fatigue cracks initiation at many rivet locations simultaneously is more at splice joint. This paper has relevance in the structural integrity evaluation of aging transport aircrafts structural segment due to multisite damage.Finite element analysis of the Fuselage segment will be carried out to obtain the stress distribution near the joint. Fatigue cracks will emanate from the rivet holes simultaneously as they experience identical stresses due to internal pressure. In service the cracks in the fuselage will grow due to pressurization loading cycle (the difference in internal pressure and the atmospheric pressure at various altitudes). This study reveals the failure mechanics of the net section between the two advancing crack tips.There are two competing mechanism of failure; Failure due to fracture and Failure due to net section yielding (plastic collapse). The mode of failure will depend on which of the above two occurs at a lower load. The stress intensity factor calculations are carried out by using Modified Virtual Crack Closure Integral (MVCCI) method. The stress analysis is done using Nastran & Patran. The results were in compatible.