The techniques of the method of the coupled modelling was substantially extended and used for solving problems connected with underground constructions for various materials and appropriate structural systems. In principle, a combination of linear effects of the external loading and material and time-dependent nonlinear change in structures was considered. Assessment of rock behaviour in surrounding of utility tunnels, solution of the structural strength below foundation, back analysis of reinforced soil slopes and studies of slopes endangered by groundwater were carried out., Petr Procházka and Jiřina Trčková., and Obsahuje bibliografii
The paper deals with stress concentration in inclined bars and beams, where the shoulder radius is often not prescribed in the detail drawings. The commonly accepted notch definition as a stepwise change of the beam cross section, as well as a lack of
nomograms or other data on stress concentration in inclined shoulders in the available literature ([1], [2], [3]) support the assumption of negligible stress concentration in inclined shoulders. Several failures of shaft-like components with inclined shoulders made us to investigate the stress concentration in these shoulders. Computational modelling confirmed a rather high stress concentration even in shoulders with a very low inclination β angle. Even in the case of β = 30°, the stress concentration factor is only slightly lower than in a comparable perpendicular (β = 90°) shoulder. Therefore nomograms for evaluation of stress concentration factors in inclined bar and beam shoulders under basic loading types were created and published in the paper.
The contribution deals with finite element analysis of stress state in sub-sized pre-cracked three-point bend specimen (KLST). A studied material was Eurofer ‘97 steel. The true stress-true strain curve was obtained from tensile test. The three-point-bend tests were carried out on pre-cracked plain and side-grooved specimens at ambient temperature. Performed tests were simulated using FEA software ABAQUS 6.10. The stress state in KLST specimen was compared with the stress state of pre-cracked Charpy and 1T SENB. The analysis confirmed the stress state of standard fracture toughness determination because loss of crack-tip and out-of-plane constraint. and Obsahuje seznam literatury
This review deals with the stress strain analysis of the normal tibio-femoral joint in its basic position (extension). On the basis of the analysis, a contact pressure between a femoral and tibial cartilage and femoral cartilage and meniscus has been obtained. The geometry of bones (tibia and femur) was described by computer tomography and the shape of cartilage and meniscus was created with the aid of literature [1], [3], [16]. The system was loaded by displacement. Following the Ansys analysis, force representing the load within the knee joint area has been determined. and Obsahuje seznam literatury
In case of a traumatological contusion of the elbow joint the bearing surfaces of the proximal end of the radius are damaged or broken off, resulting in their surgical removal. This operation does not make the elbow connection non-functional; however, it results in shortening the antebrachial bones, causing unpleasant pain in the patient‘s wrist. The medical team of the Traumatological Hospital in Brno has asked us to come up with a partial radio-humeral alloplasty, eliminating such adverse effects.
In this study, we tested the hypothesis that experimental stress induces a specific change of left-right electrodermal activity (EDA) coupling pattern, as indexed by pointwise transinformation (PTI). Further, we hypothesized that this change is associated with scores on psychometric measures of the chronic stress-related psychopathology. Ninety-nine university students underwent bilateral measurement of EDA during rest and stress-inducing Stroop test and completed a battery of self-report measures of chronic stress-related psychopathology. A significant decrease in the mean PTI value was the prevalent response to the stress conditions. No association between chronic stress and PTI was found. Raw scores of psychometric measures of stress-related psychopathology had no effect on either the resting levels of PTI or the amount of stress-induced PTI change. In summary, acute stress alters the level of coupling pattern of cortico-autonomic influences on the left and right sympathetic pathways to the palmar sweat glands. Different results obtained using the PTI, EDA laterality coefficient, and skin conductance level also show that the PTI algorithm represents a ne w analytical approach to EDA asymmetry description., M. Světlák ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
The presented paper is focused on the stress-strain analysis of the restored tooth. For this problem computational modelling was chosen using the finite element method. The tooth is modelled from dentin and dental enamel with a class II cavity. The size of the dental cavity is considered in three sizes and three shapes. For restoration two types of filling materials were used. A physiological model of the tooth was created as well. Force was prescribed on the occlusal surface of the tooth. The analysis of results shows that from the different filling materials, and their interaction with the dental tissues, amalgam is from a mechanical aspect the best material for the restored tooth in the molar segment. and Obsahuje seznam literatury
The strength and stiffness of the differential cage is very important issue, because it affects the functionality of the other components of powered axles. The problem is that for the stress analysis of the differential cage is not possible to use conventional strength and elasticity approaches, because the differetial cage has very complex geometrical shape and is also loaded by the combination of forces generated by the load engagement of the bevel gear. Therefore numerical simulations are more and more frequently used to solve this complex problem when the main task is creation the computational model that correspond the real state. The present paper deals with designing the computational model of the cage differential drive of the rear powered axle of utility vehicle. This model is then used for the strength structural analysis of the differential cage assembly. Presented computational model takes into account also the load of the differential cage thanks to the preload in strength bolts which join the bevel crown gear and differential cage. and Obsahuje seznam literatury a názvosloví