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This paper presents the experimental justification of the applicability of a rapid method for the life assessment of heat-resistant steels under cyclic loading in a multiaxial stress state with consideration of metal damage. [ABSTRACT FROM AUTHOR]

The paper presents results of an analysis of the gas-dynamic control of flow around the guide blades of axial compressor stage for the vibration intensity of rotor blades. It has been shown that gas-dynamic action on flow around blades equalizes the flow velocity field before the rotor and reduces the level of resonant stresses in blades in the case of their resonant excitation. [ABSTRACT FROM AUTHOR]

The paper addresses the mechanical behavior of carbon steel 20 in asymmetric loading under the conditions of plane stress state that occurs in a thin-walled specimen in tension-compression and alternating torsion. The asymmetric cyclic loading of specimens was carried out in a stress-controlled mode along three paths with a frequency of 0.1 Hz with a base up to 1200 cycles. Cyclic stress-strain diagrams have been constructed for the specimens under tension-compression, alternating torsion, and proportional loading. The curves of von Mises equivalent ratcheting strains have been plotted. The highest ratcheting rate is shown to take place in the tension-compression loading case. [ABSTRACT FROM AUTHOR]

The paper provides some results of the investigation of the influence of stress state type on accumulation of dispersed damages in structural carbon steel sheet under repeated static biaxial tensile loading. It is shown that the lowest damage accumulation ability of the metal is observed under biaxial tension with a biaxiality index ranging between 0.25 and 0.3. [ABSTRACT FROM AUTHOR]

The paper outlines the methodological approach and the related software package, which permit determining stress-strain state and defect rate for full-scale crack-containing objects. The method is based on computational assessment of the above-mentioned parameters on the condition of minimum of the objective function that describes discrepancy between the experimental data arrays and the results of numerical solutions to model problems using the finite-element method. [ABSTRACT FROM AUTHOR]

The paper addresses the well-known (from available publications) phenomenological strength criteria for anisotropic materials, which are most widely used in application software. [ABSTRACT FROM AUTHOR]

The aim of this finite element stress analysis (FEA) study was to assess the effect of separated files (SF) that were broken at two levels (at apical 4 and 9 mm) on the biomechanics of premolars and to determine if removal techniques affect stresses. Six lower premolar teeth were screened on computerized microtomography (micro-CT), standard access cavities were prepared, working lengths were determined, and root canals were prepared (Protaper files, Protaper Universal, Dentsply, Switzerland). Notches were created on the final shaping-file F3 at points 4 and 9 mm from the file tips, inserted in the canals, and squeezed at the apical to break. The roots were rescreened, and SFs were removed by using a Masseran kit (MK; Micro Mega, France), ultrasonic tips (UT; Satelec, Acteon group, France), and the bypass (BP) technique. Final scans were obtained and converted into three-dimensional FEA models. The following conditions were then simulated: a) root-filled tooth with SF; b) root-filled tooth after removal of the SF by using MK, UT, or BP techniques. The models were loaded axially (from two directions) and vertically (300 N), and von Mises stresses were then analyzed. SFs increased the stresses within the root. Longer SFs cause higher stresses within the root and thus should be removed, while short SFs could be kept considering the other clinical factors. Removal via MK caused the highest stresses within the roots among the techniques used. Axial loading caused higher stresses at the cervical side, while the stresses moved toward the apical side under vertical loading. SFs increase the stresses within the root. Long SFs should be removed while short SFs can be left (considering other clinical factors that may affect the success of the treatment). Removing short SFs located at the apical side negatively affects the biomechanics of the teeth, and this effect is more dramatic with the MK technique. [ABSTRACT FROM AUTHOR]

The mechanical characteristics of granular matter tested under biaxial loading are studied by numerical simulation. The stress-strain process, volume strain, coordination number, and shear zone are analyzed. The results indicate that the shear zone develops along with the coordination number and volume strain. With an increase in strain, the shear zone is centralized gradually. Moreover, the force transfer in the granular matter is also discussed. [ABSTRACT FROM AUTHOR]

The authors present the calculation results for the stress-strain state of the weldment of the 'hot'collector to the nozzle in the PGV-1000 steam generator in the area of welded joint No. 111 in the simulation of the seismic loading specified using the response spectra for the vertical and horizontal vibrations. The calculation of seismic stresses is performed based on the linear-spectral analysis using the three-dimensional model of the WWER-1000/338 reactor plant. [ABSTRACT FROM AUTHOR]

Results are presented for both the calculated assessment of the residual manufacturing stress fields in the simulation of the heat treatment in the vicinity of welded joint No. 111, and the calculation analysis of operating stresses and the fracture resistance of the collector-to-nozzle welded joint in the PGV-1000M steam generator in the simulation of the operating loading cycle. [ABSTRACT FROM AUTHOR]

method for calculating the fields of parameters of the stress-strain state at the crack tip for mixed modes of loading is developed and implemented taking into account the higher-order terms. The influence of the final crack tip curvature radius on the parameters characterizing the mixed failure modes under plane strain is shown. The nature of influence of the mixed modes of loading and the crack geometry on the behavior of dimensionless angular characteristics of the second term in the expansion of the stresses in the plastic crack tip region is established from the calculation results. The relationships between the mixing, constraint and triaxiality parameters are derived in a full range of mixed deformation modes. [ABSTRACT FROM AUTHOR]