scholarly journals Model of the dynamics of a shallow tunnel under the action of a traffic load

2020 ◽  
Vol 133 (4) ◽  
pp. 28-39
Author(s):  
L.A. Alexeyeva ◽  
Keyword(s):  
Half Space ◽  
Strain State ◽  
Computer Experiments ◽  
Elastic Half Space ◽  
Traffic Load ◽  
Elastic Cylindrical Shell ◽  
Shallow Tunnel ◽  
Stress Strain ◽  
Transverse Waves ◽  
Stress Strain State

A mathematical model has been developed for the effect of an arbitrary transport load on a shallow tunnel, supported by a multilayer elastic cylindrical shell located in an elastic half-space. The displacement of the layers of the shell and the elastic half-space is described by the Lame equations in a moving coordinate system. An analytical solution is obtained for the problem of determining the components of the stress-strain state of a rock mass and a shell at arbitrary loading speeds in the subsonic case, when the transport load moves at a speed lower than the propagation velocities of longitudinal and transverse waves in the rock and shell. The results of computer experiments are presented, which illustrate the stress-strain state of pipelines and the earth's surface under moving traffic loads.

NUMERICAL INVESTIGATION OF THERMOMECHANICAL PROCESSES UNDER SHORT-PULSED LASER IRRADIATION OF A HALF-SPACE

2021 ◽  
Vol 6 ◽  
pp. 55-65
Author(s):  
Kamila Storchak ◽  
◽  
Nina Yakovenko ◽  
Olga Polonevych ◽  
Irina Sribna ◽  
...  
Keyword(s):  
Residual Stress ◽  
Laser Irradiation ◽  
Half Space ◽  
Strain State ◽  
Thermal Stresses ◽  
Equations Of Motion ◽  
Thermomechanical Loading ◽  
Stress Strain ◽  
Stress Strain State ◽  
Residual Strains

The laser irradiation of metallic surfaces by intense heat sources is used for the generation of short probing pulses, which propagate into thin specimens and enable one to estimate their structure and mechanical properties within the framework of the classical acoustic approach. High thermal stresses and residual strains occur during the short-term irradiation of the surface of a construction by an energy source of high density. In the present work, we solve the axially symmetric problem of a half-space under thermomechanical loading. We take into account the influence of volume and inelastic characteristics of separate phases on the residual stress-strain state of the half-space. The statement of the problem includes: Cauchy relations, equations of motion, heat conduction equation, initial conditions, thermal and mechanical boundary conditions. The thermomechanical behavior of an isotropic material is described by the Bodner-Partom unified model of flow. The problem is solved with using the finite element technique. The numerical realization of our problem is performed with the help of step-by-step time integration. The equations of motion are integrated by the Newmark method. The residual stress-strain state is described using the method of numerical solution of the axisymmetric dynamic problem for a half-space under thermomechanical loading and the flow model. We established that microstructural transformations, which are taken into account due to the thermophase volume strain and dependence of inelastic characteristics of the material on the phase composition, significantly reduce residual inelastic strain and promote the appearance of compressive stresses. The three-zone region of residual stresses field formation is obtained.

Indentation of the cylindrical shell in the elastoplastic half-space

2018 ◽  
Vol 13 (3) ◽  
pp. 47-51
Author(s):  
A.A. Filippov
Keyword(s):  
Cylindrical Shell ◽  
Stress State ◽  
Half Space ◽  
Safety Factor ◽  
Strain State ◽  
Fracture Criterion ◽  
Steel Shell ◽  
Stress Strain ◽  
Stress Strain State ◽  
Steel Cylindrical Shell

The article deals with the problem of pressing the steel cylindrical shell into the elastoplastic half-space having a cylindrical concavity. The calculation and analysis of the stress-strain state of the steel shell and elastoplastic half-space. Given the dependence of the shear half-space, the safety factor and stress state in steel shell from the force pushing the shell in the half-space. The calculations were carried out for three radii of concavities and two types of half-space materials. It was assumed that the elastoplastic half-space obeys the Mohr-Coulomb fracture criterion.

Stress-strain state of a half-space in the neighborhood of a stiff sphere subjected to a normal load

1988 ◽  
Vol 24 (4) ◽  
pp. 331-336
Author(s):  
I. K. Senchenkov ◽  
V. I. Kozlov ◽  
I. G. Rubtsova ◽  
A. B. Oleinikov
Keyword(s):  
Half Space ◽  
Strain State ◽  
Normal Load ◽  
Stress Strain ◽  
Stress Strain State
Sign in / Sign up

Export Citation Format

Share Document