This paper presents a model-based monitoring framework for the detection of fatigue-related crack damages in plate-type structures commonly seen in aluminum ship hulls. The monitoring framework involves vibration-based damage detection methodologies and finite element modeling of continuum plate structures. A Bayesian-based damage detection approach is adopted for locating probable damage areas...

This paper considers a dynamical system subjected to damage evolution in variable operating conditions to illustrate the reconstruction of slow-time (damage) dynamics using fast-time (vibration) measurements. Working in the reconstructed fast-time phase space, phase space warping-based feature vectors are constructed for slow-time damage identification. A subspace of the feature space correspon...

This study proposes a simulation method to evaluate fatigue progressive damage in composite laminates using intra-laminar and inter-laminar models. The damages are modeled continuum mechanics cohesive zone model, respectively, the evolution laws of formulated. A combining finite element models described this paper. Fatigue simulations conducted on curved specimen results that compared with expe...

Although fatigue damage in bone induced by cyclic loading has been recognized as a problem of clinical significance, few fracture mechanics based studies have investigated how incipient cracks grow by fatigue in this material. In the present study, in vitro cyclic fatigue experiments were performed in order to quantify fatigue-crack growth behavior in human cortical bone. Crack-growth rates spa...

Application of cyclic loading results in the formation of distinct strain-dependent microdamage morphologies. It is still unknown; however, how the morphology of microdamage affects age-related increase in bone fragility. In this study, four-point bending fatigue tests were conducted on aging human bone (age 26 to 89) in conjunction with histological evaluation of the resultant tensile (diffuse...

In this study static and fatigue behaviours of honeycomb sandwich composites, made of aramide fibres and aluminium cores, are investigated through four-point bending tests. Damage and failure modes are reported and discussed. Global and local parameters were considered to evaluate the fatigue life of the analysed sandwich composites. Effects of core densities and the cell orientation (L or W) o...

To date the term “Fatigue Damage” has had an ambiguous usage in fatigue community. This paper explains reason for poor predictive results of existing damage rules, such as Miner’s rule, through precise observation small crack growth during multiple step loadings. For exact evaluation it is crucially important to attend phenomenon continuous decrease limit with until final failure. It stress amp...

Fatigue life estimation is one of the most important design considerations in mechanical parts which are subjected to alternating loads. When loads act along several axes, multiaxial fatigue approach should be used to obtain more accurate results than uniaxial fatigue method. In this paper stress analysis of the steel shaft of a high speed microgenerator rotor with 47750 rpm and 100kW is carrie...

Shear banding is a ubiquitous phenomenon of severe plastic deformation, and damage accumulation in shear bands often results in the catastrophic failure of a material. Despite extensive studies, the microscopic mechanisms of strain localization and deformation damage in shear bands remain elusive due to their spatial-temporal complexities embedded in bulk materials. Here we conducted synchrotro...

The purpose oi' the study was to investigate, through laboratory tests, the potential for developing fatigue indicators for which some merit was evident from prior research. The response of photographic emulsions, phosphor coatings,and chemical indicator coatings to physical and surface-chemical reactions associated with fatigue damage in 2024-T3 aluminum was investigated. Many indicators were ...