Открытый доступ
Доступ предоставлен
Только для подписчиков
Том 72, № 5 (2017)
- Год: 2017
- Статей: 6
- URL: https://journals.rcsi.science/0027-1330/issue/view/10015
Article
Asymptotic behavior of creep curves in the Rabotnov nonlinear heredity theory under piecewise constant loadings and memory decay conditions
Аннотация
Some minimal prior constraints are imposed on the two material functions used in the Rabotnov nonlinear constitutive relation. The asymptotic dependence of creep curves on the characteristics of these material functions and on the parameters of loading programs is analytically studied in the case of stepped loadings. Some conditions are obtained for the case when these curves tend to the creep curve under instantaneous loading as t→∞. The importance of the limit value of the creep function derivative at infinity is analyzed for the plastic strain accumulation. A number of distinctions and additional possibilities are found compared to the linear integral relation of viscoelasticity.
103-107
Stress–strain measures used in the ANSYS package to solve elastoplastic problems at finite strains
Аннотация
It is shown that the Dienes (or the Green–McInnis–Naghdi) derivative is used in the ANSYS package rather than the Jaumann derivative as an objective derivative for the Cauchy stress tensor when solving elastoplastic problems, although the usage of the Jaumann derivative is stated in the ANSYS theory reference manual. In this manual it is also stated that, for these problems, the strain tensor is the Hencky logarithmic strain tensor; however, in reality, this strain tensor is the right nonholonomic strain tensor such that the left nonholonomic strain tensor associated with the right one is generated by the Dienes derivative.
108-112
The synthesis of an inhomogeneous elastic system with a boundary load
Аннотация
For an adequate description of free and controlled motions of one-dimensional elastic systems with distributed parameters, we consider a suitable model expressed by a linear problem with Robin boundary conditions. It is assumed that the control action is used additively in the equation of motion and in the boundary conditions. The coefficients used in the equation of state and in the boundary conditions may depend on the spectral parameter (frequency), which allows one to take into account the inertial and/or force load at one or both ends of the boundary as well as the elastic properties (the Rayleigh correction) and other imperfections.
113-118
119-123
124-125
126-127