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Copyright of Movement & Sport Sciences / Science & Motricité is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Psycho-Oncologie is the property of Tech Science Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Matériaux et Techniques is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Matériaux et Techniques is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Psycho-Oncologie is the property of Tech Science Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Mechanical and structural components are subject in the most cases during their services to random loading. For this reason, it is necessary to reduce the complex history of these kinds of loading in a series of constant amplitude cycles. There are several counting methods that lead to different results. Among all these methods, it is recognized that the Rainflow Cycle Counting method provides the most conservative results. In this paper, a finite elements analysis technique is presented to predict the fatigue life using this method associate with the S-N method which is used for high cycle fatigue applications that makes no distinction between initiation or growing a crack, but rather, predicts the total life to failure. Comparison between numerical and experimental results is considering in this paper.

The physical load increase during training can lead to the development of clinical patterns of intolerance differing according to their severity, prognosis and reversibility. However, they always include fatigue as a key symptom. The aim of this paper is to review recent data on fatigue states in sportsmen, their clinical presentation and diagnostic orientations. A continuum exists, from acute fatigue states after one or several highly-intensive training sessions, to overreaching, associated to performances alteration which can be easily reversed, and to overtraining, representing a severe clinical pattern which can hardly be reversed. Overreaching and overtraining are characterized by a persisting fatigue state, associated to performances alteration and mood disorders. In an athlete with unexplained alteration of performances associated to physical fatigue, the medical interrogation is critical, in order to check the durable character of sportive performances alteration, to describe the fatigue and identify risk factors of occurrence of overtraining (training program intensity, mental stress, diet factors, hypoxic training, etc.). The use of a validated and adapted questionnaire as the one proposed by the French Society of Sports Medicine is valuable. In majority, in athletes and those doing sports regularly, the cardiological alert signs are rare, and the clinical examination by a specialist is poorly contributive, except for eliminating an organic cause of fatigue.

Objective: To review the literature on fatigue in ankylosing spondylitis (AS), the tools of its measurement, relation with the other parameters of the disease, treatment and its relation with exercises., Materials and Methods: Medline, Embase, Pascal and Cochrane library databases were searched with the keywords fatigue, spondyloarthropathy, ankylosing spondylitis, evaluation, assessment, outcome, exercise, and rehabilitation. A total of 21 papers were reviewed., Results: Fatigue is a frequent complaint of patients with AS. It is assessed mainly on a visual analog scale and is one of the parameters of the disease activity index Bath Ankylosing Spondylitis Disease Activity Index BASDAI. Fatigue has a strong relation with the other symptoms of AS (stiffness and pain). It is negatively influenced by sleep disorders. Quality of life of these patients is considerably reduced. Anti-TNF therapy seem to ameliorate fatigue more than nonsteroidal anti-inflammatory drug therapy. Regular physical activity is recommended to help alleviate the fatigue., Discussion: No valid, relevant composite tool of multidimensional and multifactorial characters exists to assess fatigue in AS. Treatment such as anti-TNF therapy may facilitate rehabilitation. Regular physical activity helps alleviate fatigue and improves quality of life.

Copyright of Canadian Journal of Civil Engineering is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cables currently used in civil engineering, including cable-stayed bridges or suspension bridges, are made of cylindrical steel wires with a diameter between 3 and 7 mm. They are unalloyed or low alloyed steel whose composition is near eutectoid and are obtained by cold drawing. They have a high resistance in traction (more than 1900 MPa) and a low ductility. By their constitution, cables have high tensile strength and low bending stiffness. However, the studies conducted in recent years have shown that the main causes of cables deterioration are due to corrosion and to inter-wires frictions induced by fatigue. These cables degradation mechanisms are described in this paper. Different methods of protecting civil engineering cables were originally developed against corrosion, such as metal coatings (galvanization, galfanization), and lubrication. These protections can also have effects on fatigue. The experimental and numerical results obtained from single wires and presented in this paper, show obviously the beneficial effect of galvanizing and lubrication in terms of fretting fatigue lifetime. However, the mechanisms of degradation due to fretting fatigue in the presence of corrosion are not fully known and are currently the subject of a thorough study. [ABSTRACT FROM AUTHOR]

The study presented in this paper is part of a project aiming at evaluating the potential use of aluminum in structures. The types of intervention could range from a simple repair or a reinforcement involving structural aluminum, the replacement of a used bridge deck by an aluminum deck, to the construction of a new bridge made in full or in part of aluminum. It is this latter type of intervention that justified a research project, the results of which are presented in this article. The first step involves identifying the most advantageous type of aluminum structural system from a structural standpoint as well as an economic standpoint. This step includes the analysis and partial design of 40 girder- or truss-type road bridges, spanning 15 and 35 m, supporting either an active concrete slab or an aluminum deck. These studies have shown that bridges built using a Pratt-type truss and an active concrete slab provided the best results. It is also shown that some calculation criteria, such as vibration, deflection, and fatigue criteria limited the extensive use of aluminum in bridges. In the second step, nine bridges are more comprehensively analysed and designed, based on the standards used in North America, and three are fully designed, including the connexions, in order to realize a cost analysis study that is as accurate as possible. Special attention is given to vibration and fatigue problems as well as to the details related to connexions calculation. The study concludes that the development of an aluminum-only medium span road bridge system is a non-viable project in the short to mid term from a structural standpoint as well as an economic standpoint, and it makes recommendations on the use of aluminum decks and on the continuation of the work.Key words: aluminum, analysis, bridges, connexions, design, fatigue, standards, vibration.[Journal translation]L'étude présentée dans cet article s'inscrit dans le cadre d'un projet visant à évaluer le potentiel d'utilisation de l'aluminium dans les ouvrages d'art. Le type d'intervention peut être une simple réparation ou un renforcement impliquant de l'aluminium structural, le remplacement d'un tablier de pont usagé par un tablier en aluminium ou, encore, la construction d'un nouveau pont entièrement ou en grande partie en aluminium. C'est ce dernier type d'intervention qui a justifié le projet de recherche dont les résultats font l'objet de cette présentation. Une première étape vise à identifier le type de système structural en aluminium le plus avantageux, tant du point de vue structural que du point de vue économique. Cette étape comprend l'analyse et le dimensionnement partiel de 40 ponts routiers de types poutres pleines ou à treillis, de 15 et 35 m de portée et supportant soit une dalle de béton participante, soit un tablier en aluminium. Ces travaux ont démontré que les ponts ayant des poutres triangulées de type Pratt et une dalle participante en béton armé présentent les meilleurs résultats. Il en ressort aussi que certains critères de calcul, tels les critères de vibration, de flèche et de fatigue limitent grandement l'utilisation de l'aluminium dans les ponts. Dans une deuxième étape, neuf ponts sont analysés et dimensionnés plus finement sur la base des normes en vigueur en Amérique du Nord et trois sont dimensionnés au complet, y compris les assemblages, dans le but de réaliser une étude comparative des coûts la plus précise possible. Une attention spéciale est portée aux problèmes de vibration et de fatigue ainsi qu'aux particularités du calcul des assemblages. L'étude conclut que le développement d'un système de pont routier entièrement en aluminium, de moyenne portée, est un projet non viable à court ou à moyen terme, tant du point de vue structural que du point de vue économique et fait des recommandations sur l'utilisation des tabliers en aluminium ainsi que sur la poursuite des travaux.Mots clés : aluminium, analyse, assemblages, dimensionnement, fatigue, normes, ponts, vibration. [ABSTRACT FROM AUTHOR]

The bonding at the interface is seen in most road structure design methods as perfectly bonded and this ideal condition is supposed to last during the whole service life. However, the real working capacity at the interface is complex and gradually degrades because of repeated traffic load and weather conditions. A new apparatus called 2T3C (“Torsion, Traction, Compression sur Cylindre Creux” in French, or “Torsion, Tension, Compression on Hollow Cylinder” in English) was developed at the ENTPE/University of Lyon to investigate the thermomechanical behaviour of the interface between bituminous layers. The sample has two layers of similar or different materials. It has a total height of 125 mm and a wall thickness of the 25mm. The thickness was chosen small enough in order to validate the assumption of quasihomogenous stress and strain fields between inner and outer surface. The DIC technology is performed considering the three listed elements: (1) two couple of cameras are situated on two opposite sides of the sample (4 cameras in total) to take 3D images; (2) a software is employed to calculate the displacements in 3 dimensions of all points in the area of interest; and (3) the strain fields in the 2 layers and the displacement gap at the interface are computed using a method developed at the University of Lyon/ENTPE. In this paper, a focus is proposed on the viscoelastic and fatigue behaviours of the two bituminous layers and of the interface. Small and large numbers of loading cycles are successively considered in the small strain domain.

Copyright of Travail Humain is the property of Presses Universitaires de France and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents an accelerated test method applicable to complex mechanical devices when no analytical relationship with respect to the stress level can be defined. If a numerical approach remains possible, the numerical model can be fitted to the accelerated test results. Thus, long term failures can be predicted from very short tests. This method is carried out in the case of fatigue, the evolution of the damage leading to the failure having to be modeled by a numerical finite-elements method. [ABSTRACT FROM AUTHOR]

In this paper, a modified direct current potential drop (DCPD) method for real-time measurement of the length, the inclination and the position of cracks is presented. Based on the proposed configuration, it is possible to process the data acquired by continuously measuring the change in the electrical resistance (potential drop) between specific points on the specimen in real time and correlate them with the propagation of the crack and thus identifying its crucial characteristics. Furthermore, many aspects that affect the electromagnetic field inside materials have been identified. In that way the influence of unwanted factors can be significantly reduced which has led to a better understanding of the relation between the implemented voltage values and the fracture itself. Therefore, conclusions are drawn about the structural integrity of any given specimen through a risk assessment after the crack characteristics have been calculated. In order to achieve this, a variety of techniques were implemented including the development of a stochastic algorithm along with a customized experimental layout so as to accomplish high accuracy for the prediction model as well as robustness towards other influencing parameters such as temperature and humidity.

This paper presents fatigue property of CFRP-strengthened cracked steel plate. Firstly, the finite element model of CFRP-strengthened cracked steel plate is established by using the cohesive zone model. With the finite element model, stress intensity factor of the crack-tipis calculated. Then, it gives the fatigue tests of cracked steel plate. According to the experimental data, the material constants C and n value sare obtained. The prediction fatigue life is calculated by the finite element model and Paris function and verified by the experimental data. The results show that the prediction fatigue life, calculated by the finite element model and the Paris formula, is consistent with the experimental fatigue life, which verifies the accuracy of our prediction model with finite element model and the Paris function.

The paper deals with the fatigue damage calculation of 2 types of computation model of bolted joints. The study is performed via a numerical analysis with support of finite element method (FEM) software ANSYS. One model was created with a thread on the bolt, another was only bolt with cylindrical surfaces, the second model was greatly simplified. It will be evaluated the fatigue damage for both types of models. Subsequently both types of computational models will be compared in dependence on the accuracy of the results and the speed of the calculation. There are also the theoretical backgrounds for preloaded bolted joint, which was used for calculation of preload load prescribed on body of screws.

Presented paper focuses on intermediate outcomes of the bilateral project between the Faculty of Mechanical Engineering, STU in Bratislava, Slovakia and the Institute of Automotive and Transport Engineering, UBFC in Nevers, France. Thus, mechanical properties and behaviour of glass fibre reinforced polymer composite foam cored sandwich panels joints were researched to estimate the best possible joint technology. Three-point bending and four-point bending were used to evaluate flexure strength and static force-flexure curve. Based on such testing, one specific joint composition was chosen to be broadly investigated. Finally, chosen type of joint panels was tested under four-point cyclic loading to obtain its fatigue properties.

In the production of semi-finished products for the production of microcomponents and the components themselves, the characterization of their physical properties is of particular importance. Due to the often oligocrystalline character of these semi-finished products and components, it is necessary to use a suitable testing technique for static and dynamic investigations, as the mechanical properties are not transferable from the macroscopic point of view. In addition, the micro semi-finished products and components often show inhomogeneities induced by the manufacturing process. On the one hand, these are directly reflected in the microstructure and on the other hand they have an effect on quantities such as hardness or residual stresses, which play a decisive role in the application. Mechanical testing, conventional metallography, scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), ultra-microhardness testing and X-ray residual stress analysis were used as measuring and analysis techniques suitable for the sub-millimeter range. In the following, the possibilities and limitations of two these methods are illustrated using the example of mechanical testing and EBSD. In this paper several examples for possible characterization techniques are given.

This paper presents the results of an analysation of forming damage during the joining process on the fatigue failure behaviour of a clinched connection. The two joining partners out of aluminium, AlMg0.7Si on the punch side and AlMg3 on the die side, are clinched with a flat clinching system and the use of a preformed hole at the die side. By the use of two different geometry variants it could be shown, in fatigue Wöhler tests, that the fatigue failure behaviour is influenced by the material damage in the deformed material of the clinch. The material damage during the clinching process could be calculated with the help of FE-Simulations. So it was possible to show that more forming damage during the joining process causes less lifetime of the connection.

Copyright of Movement & Sport Sciences / Science & Motricité is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Matériaux et Techniques is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revue Francophone de Psycho-Oncologie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)