NASA has conducted an Airframe Structural Integrity Program to develop the methodology to predict the onset of widespread fatigue damage in lap-splice joints of fuselage structures. Several stress analysis codes have been developed or enhanced to analyze the lap-splice-joint configuration. Fatigue lives in lap-splicejoint specimens and fatigue-crack growth in a structural fatigue test article a...

Since thin-walled composite structures are widely used in structural engineering, damage in such structures is an important issue of research. Matrix cracking is a principal cause of failure in composites. In the present study, a composite matrix cracking model is implemented in a thin-walled hollow circular cantilever beam using an effective stiffness approach. Such structures are used to mode...

The generation and the subsequent evolution of dynamic failure events in homogeneous layered materials that occur within microseconds after impact were investigated experimentally. Tested configurations include three-layer and two-layer, bonded Homalite specimens featuring different bonding strengths. High-speed photography and dynamic photoelasticity were utilized to study the nature, sequence...

The dynamic propagation of a bifurcated crack under arbitrary loading is studied. Under plane loading con2gurations, it is shown that the model problem of the determination of the dynamic stress intensity factors after branching is similar to the anti-plane crack branching problem. By analogy with the exact results of the mode III case, the energy release rate immediately after branching under ...

The force required to peel a film from a substrate is generally a complex function of geometry, the constitutive properties of the film and substrate, and the interfacial cohesive properties. In most analyses, the effects of the transverse shear force that is an integral aspect of almost any peel test are neglected, although they can be incorporated in an indirect fashion through models that in...

in this study, displacement field around v-notches of a poly methyl metha crylate (pmma) specimen with tip cracks will be analyzed using digital image correlation technique. first intensity factor in combination with in-plane rigid body translations and rotation components will be determined by linear least squares fitting of the displacement field data to the corresponding relations among stre...

In order to solve the impact on accuracy of a life prediction model when initial crack angle curved surface is not 0°, traditional stress intensity factor revised by non-linear regression analysis method, and an optimized growth established. This paper takes bottle neck pressure vessel as research object, uses finite element method establish simulation with 0°. By analyzing factors different st...

This paper concerns the effect of friction on crack propagation for centrally cracked Brazilian disk under diametric forces by using a modified finite element method. It shows that mode II stress intensity factor decreases obviously with increase after is closed, while has no influence I and T-stress. Meanwhile, there are some significant influences due to change closed appropriate loading angl...

The elastic-plastic behavior of the material is considered to analyze the effect of an external circumferential crack on a pipe with thickness transition and double slopes. Using the extended finite element method (XFEM), the J-integral of 3D cracks were investigated and compared between straight pipes and pipes with thickness transition and different slopes. Considering internal press...

Interfacial fracture of adhesive bonds undergoing large-scale yielding is studied using a combined experimental/ finite-element approach. The full range of in-plane mode mixity is produced over bond thickness ranging from 30 to 500 lm using the scarf and the ENF joint geometries. Novel techniques for introducing pre-cracks and surface decoration, together with in situ observations, facilitate a...