A typical dynamometer drive shaft was damaged during its working condition. This failure was repeated in four cases. In the present article, a failure analysis of a dynamometer drive shaft has been performed. To analyze the failure, the material investigation was carried out by scanning electron microscopy (SEM) images. Additionally, the micro-structure of the failed coupling shaft was photogra...

Warm mix asphalts (WMA), because of their low production and compact temperatures, may have different behaviors in long term. In the present work, the energy-based criteria along with the 50% reduction in initial stiffness (Nf50%) using four-point bending test under controlled-strain conditions of 1000 microstrain were applied to compare the prepared two warm mix and HMA samples. All these crit...

Free-span occurs normally in a pipeline at uneven seabed, dynamic seabed and pipeline crossing. Free spanning in pipeline causes Vortex Induced Vibration (VIV) fatigue, fracture and bursting. In this paper, a pipeline located in South Pars Gas Field is assessed against local buckling and VIV fatigue using probability of failure theory based on the recommended methodology by Det Norske Veritas (...

because of inhomogeneity and anisotropy of composite materials, defining a unique fatigue criterion to be suitable for different loading conditions is much more difficult in comparison with traditional materials. for this reason many tests on evaluating the damages such as crack density, stiffness reduction and residual strength are used by various researchers to monitor the fatigue process. in...

objectives: the purpose of this study was to evaluate the resistance to fatigue failure of five different nickel-titanium rotary files in three different curved trajectories. materials and methods: a total of 150 neoniti a1, race 25.06, mtwo 25.06, twisted file 25.06 and protaper next x2 files with the tip size of 25 were tested (n=30 for each group). three groove types simulating curved canals...

As cyclic fatigue is considered to be a major cause of clinical tooth fractures, achieving a comprehensive understanding of the fatigue behavior of dentin is of importance. In this note, the fatigue behavior of human dentin is examined in the context of the Kitagawa-Takahashi diagram to define the limiting conditions for fatigue failure. Specifically, this approach incorporates two limiting thr...

AIMS AND OBJECTIVES The purpose of this study was to examine the level of fatigue perceived by patients with heart failure and to explore the potential factors influencing fatigue. DESIGN A cross-sectional, correlational design was used. METHODS A convenience sample of 105 patients was recruited between July and September 2003 in northern Taiwan. The patients were interviewed, and their per...

When subjected to alternating stresses, most materials degrade, e.g., suffer premature failure, due to a phenomenon known as fatigue. It is generally accepted that in brittle materials, such as ceramics, fatigue can only take place in toughened solids, i.e., premature fatigue failure would not be expected in materials such as single crystal silicon. The results of this study, however, appear to...

this research work is devoted to the investigation on the use of silica on the fatigue-to-failure property of a tire tread compound. a reference compound was frst designed in which 60 phr carbon black was used as the reinforcing fller. while keeping the total of fller content to be constant as 60 phr, three additional compounds with 5, 10 and 20 phr silica were then manufactured. the classical ...