SUMMARY c The concept that creep response is the result of a transient approach to a minimum strain rate continuously modified by accumulating damage has been investigated using high precision creep data. It was considered that the accumulated creep strain might be some measure of internal damage and curves of log creep strain rate against creep strain are shown to exhibit linearity at higher s...

Time-dependent creep stress redistribution analysis of thick-walled FGM spheres subjected to an internal pressure and a uniform temperature field is investigated. The material creep and mechanical properties through the radial graded direction are assumed to obey the simple power-law variation throughout the thickness. Total strains are assumed to be the sum of elastic, thermal and creep strain...

Polypropylene is one of the most common, fastest growing and versatile thermoplastics currently used to produce tanks and chemical piping systems. Even at room temperature creep is considerable for polypropylene products. The creep behavior of strains, stresses, and displacement rates is investigated in a thick-walled cylinder made of polypropylene reinforced by functionally graded (FG) multi-w...

In this study, a real and significant industrial problem in a steam power plant was investigated. Reheater tubes in boilers are under the creep and the fireside corrosion mechanism that cause some of them to fail. Since the estimation of probability of failure (PoF) and remaining life (RL) is expensive and time consuming in the deterministic methods, in this work they were evaluated using struc...

In this work, recently developed state-of-the-art symbolic multibody methods are tested to acurately model a complex railway vehicle. The model is generated using a symbolic implementation of the principle of the virtual power. Creep forces are modeled using a direct symbolic implementation of the standard linear Kalker model. No simplifications, as base parameter reduction, partial-linearizati...

abstract: a time domain semi-analytical solution to study thermoelastic creep behavior of  functionally graded rotating axisymmetric disks with variable thickness is presented. the rate type governing differential equations for the considered structure are derived and analytically solved. to solve these  equations, the disk is divided into some virtual sub-domains. general solution of  equilibr...

Indentation creep tests and finite element simulations were performed on a model material to show that the constitutive equation for conventional uniaxial creep can be derived using the instrumented indentation testing technique. When the indentation pressure and the indentation creep rate are maintained at constant values of ps and _ 3⁄4inðsÞ, respectively, the contours of the equivalent stres...

The scatter observed in creep deformation and failure data is of considerable technological importance because it greatly complicates the task of making accurate deformation and lifetime estimates for high temperature components. In this work a stochastic model for the creep damage evolution and associated scatter has been developed in terms of a discontinuous Markov process. The magnitude of d...