A safe fatigue failure criterion is proposed relating the accumulated slip with the value of the slip at shear failure of the interface for static loading.
The fatigue failure process indicates that CFRP sheets fail when the maximum fatigue stress ( sigma_{text{f,max}}^{text{f}} ) reaches the residual strength of the CFRP ( f_{text{fr}} ); thus, the residual strength provides a safe fatigue failure criterion, which is defined by the following equation: sigma_{text{f,max}}^{text{f}}, ge, f_{text{fr}} left( n right) (21).
The propagating crack length is considered as the sole parameter to evaluate safe fatigue life, including the use of an "equivalent crack propagation rate", which averages the intense variations of CPR in the vicinity of grain boundaries.
Prediction techniques are then developed to establish the relationship equation between safe fatigue crack initiation and propagation lives with a specific reliability level using a two-stage fatigue damage cumulative rule.
On the basis of available fatigue design knowledge, the structural fatigue characteristics of hydraulic actuator was depicted based on a nominal force concept from the paucity of experimental dataset, and safe fatigue life of hydraulic actuator subjected to actual random spectrum load history was modelled based on a reliability concept.
The necessity of saving resources and improving the economic efficiency of industrial production is a strong impetus for designing new technologies and materials, which could ensure safe fatigue life of various mechanisms and structures such as bridges, railroad tracks, parts of machine and gas turbine engines, and so on, subject to about 1010 load cycles.
Practical scatter factor formulae are presented to determine the safe fatigue crack initiation and propagation lives from the results of a single full-scale test of a complete structure.
It is well known, that the orthotropic decks are sensitive to fatigue damage, therefore safe fatigue design is important for the safety assessment of bridge structures.
The paper concludes with fracture mechanics fatigue calculations to demonstrate that the information provided from the proposed equations could be utilised to obtain accurate, and safe, fatigue life estimates.
For a safe and reliable design against fatigue degradation and failure, the initiation of the main damage mechanisms (off-axis cracks, delamination and fiber failure) as well as their evolution are considered and suitable models are proposed for the quantitative assessment of the lifetime associated to each mechanism.
Our meta-analysis revealed that supervised exercise has a favorable effect on cancer-related fatigue when compared with conventional care and it can be considered as a safe therapy for the management of fatigue and other domains of quality of life in breast cancer survivors.
