In the present paper, time dependent creep behavior of hollow circular rotating cylinders made of exponentially graded material (EGM) is investigated. Loading is composed of an internal pressure, a distributed temperature field due to steady state heat conduction with convective boundary condition and a centrifugal body force. All the material properties are assumed to be exponentially graded a...

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...

Recent experimental studies of the hot isostatic consolidation of Ti-6Al-4V–coated SiC fibers contained in cylindrical canisters have revealed an unexpectedly high rate of creep densification. A creep consolidation model has been developed to analyze its origin. The initial stage of consolidation has been modeled using the results of contact analyses for perfectly plastic and power-law creeping...

Tensile creep of concrete at early ages is one of the important factors that affect the stress of restrained and partly restrained concrete. But only few data are available on tensile creep of concrete. The effect of ground slag on tensile creep was studied using lever-type tensile creep tester. Early age tensile basic creep of concrete loaded at the age of 3 days was researched. Results show t...

A set of analytical models based on engineering beam analysis is developed to predict creep behavior of cellular materials over a broad range of relative density. Model predictions, which take into account the presence of mass at strut nodes and consider different possible deformation mechanisms and foam architectures, are compared to experimental creep results for a replicated nickel-base foam...

The first part of the paper summarizes various aspects of the prediction of concrete creep and shrinkage to be discussed in the conference lecture. They include the theories of physical mechanism, prediction models, constitutive equations, computational approaches, probabilistic aspects, and research directions. The second part then presents two new prediction models. One of them deals with the...

The compressive creep and recovery of foam earplugs was studied at various applied stresses leading to different fi nal creep strains. Deformation was determined from digital videos of the earplugs via image processing software. Creep could not be modeled by a single exponential in time; creep approximated a power law in time. Nonlinear viscoelasticity was observed: creep compliance depends on ...

All three burning plasma experiments discussed at Snowmass during the summer of 2002, use preloaded structures to resist some component of the operating loads. For the resistive pulsed reactors, it is the preloads which introduce the most noticeable creep responses because these loads are applied for much longer than the operating loads. If the preloads are maintained during shut-down and maint...

A way of measuring the in situ high temperature creep deformation of a micro-structure with a metal film wire on a flexible membrane is developed. The creep deformation measurement of a micro-structure with a Karma alloy wire on a polyimide membrane is used as an application. High temperature gratings were fabricated directly on the surfaces of two Karma alloy wires using the focused ion beam m...