Abstract Wind turbines (WT) must be further optimized concerning availability and reliability. One of the major reasons WT downtime is failure gearbox bearings. Some these failures occur, due to ring creep phenomenon, which mostly detected in planetary The phenomenon describes a relative movement outer gear. In order improve understanding creep, finite element method (FEM) used simulate gears. ...

A variety of geomaterials, such as cementitious or clay-based materials, has on the nano-scale a layered microstructure that can contain fluid in its nano-porous space. The creep of such nano-scale basic units is what causes the macroscopic creep. Here, one nano-pore whose walls consist of two parallel infinite solid layers interacting through Lennard-Jones potential is studied. The authors eva...

Background: The short-time creep behavior for a series of biodegradable nanocomposites which is used as implantable device into body is a crucial factor. In the current paper, we aimed to study the effect of bioactive glass nanoparticles (BGn) on creep and creep-recovery behaviors of PLA/PCL blends at different given load and different applied temperatures. Method: A series of biodegradab...

In the Present study, attempt will be made to propose a new method for prediction of long-term essential creep of concrete utilizing some short-term creep tests under high temperature. To do so, regarding the similarities between essential creep of concrete and creep in viscoelastic materials, the time–temperature equivalence relation in viscoelastic materials is evaluated for concrete. This re...

Abstract 9-12%Cr martensitic steels are promising materials for elements of boilers, tubes, pipes, heaters and steam blades fossil power plants, which able to operate at ultra-supercritical parameters steam. Creep tests were carried out two 12%Cr 9%Cr 650°C. After tempering 750-770°C, a tempered lath structure was revealed in all the studied. The 12%Cr-Ta steel had smallest width among studied ...

This paper focuses on the effect of the viscoelasticity of the adhesive layer on the flexural creep response of reinforced concrete beams strengthened with composite materials. A theoretical model is developed, which considers the strengthened beam as a layered structure that consists of the reinforced concrete beam, the adhesive layer, and the FRP strip, and accounts for the creep of each comp...

In thermoelectric devices, Bi2Te3 must be able to operate under high temperature gradients for very long times (years) without appreciable deformation, while being subjected to stresses created by internal thermal mismatch and external forces (e.g., vibrations). The deformation rate of cast, coarsegrained Bi2Te3 was measured under uniaxial compressive stresses from 2 to 16 MPa at temperatures b...

creep phenomenon in rock engineering plays a key role in development of underground spaces as they must be stable enough for a long period of time. current research involved designing and manufacturing of a new creep testing machine. the equipment is capable to perform simultaneous light-duty creep tests on more than one cylindrical rock samples at a very low cost.to evaluate the equipment’s pe...

mechanism and factors influencing on creep behavior of clay soil have not been understood yet due to its complex structure. in this paper, to investigate the affecting parameters on the creep behavior of the clay soils such as stress level, over consolidated pressure and water pressure, odeometr test are performed in states of single stage, stepwise and overloaded-unloaded and the creep mechani...

Fluid-sheared granular transport sculpts landscapes and undermines infrastructure, yet predicting the onset of sediment transport remains notoriously unreliable. For almost a century, this onset has been treated as a discontinuous transition at which hydrodynamic forces overcome gravity-loaded grain-grain friction. Using a custom laminar-shear flume to image slow granular dynamics deep into the...