Fatigue and residual strength behaviour of ARALL3 panels with bonded-on doublers

Residual strength tests were performed on ARALL panels consisting of ARALL3 (3/2) laminates with bonded-on doublers. In particular, the effect of the doubler geometry (shape and thickness) on the residual strength was investigated. Prior to residual strength testing all panels were fatigue loaded to create a realistic type of damage, i.e. cracks...

Delamination growth in improved carbon composites under constant amplitude fatigue loading

Constant amplitude tension-compression fatigue tests were performed on notched (± 45, 02, 90, 02)s coupon specimens of the composite systems T300/F593, T400H/6376, T800H//5245C and IM6/APC-2. Delamination damage growth as a function of the number of fatigue cycles was determined using the ultrasonic C-scan technique. Considering the resistance...

Finite element analyses of stable crack growh in thin sheet material

This study deals with fracture mechanics aspects of mode 1 crack growth under montonically increasing (quasi-static) loads. Using the finite element method stable crack growth and the plastic deformation fields associated with this process are analyzed. A two parameter approach is proposed for a description of initiation and subsequent stable...

Residual strength characteristics of composite reinforced stiffened panels

Residual strength properties of carbon/epoxy composite material

Fatigue tests on unidirectional Ca/ep composite material have been performed to investigate whether previous fatigue loading did influence the residual static strength. Residual strength tests were carried out on (0, ± 45)2s and (± 45)2s laminates, while for the (O, ± 45)2s laminate the influence of previous tensile fatigue loading on the...

Residual strength data of riveted panels with different stiffener configurations

Residual strength tests were carried out on center-cracked panels with a 2024-T3 or 7075-T6 skin and provided with eccentric stiffeners of practical design. The stiffeners were riveted to the skin. The material of the stiffeners was 7075-T6. In some cases the stiffeners were combined with Ti-alloy crack stoppers. On the basis of the test results...