Investigation of the influence of the railroad track on the stress state of the tunnel lining

Abstract

Tunnel lining takes significant loads from moving vehicles. The consequences of their impact depend on the design of the railway track and the deformation characteristics of its elements. For their study, a numerical model of a circular tunnel has been developed. As a result of the model calculation, the values of the main vertical stresses in the main tunnel structures were obtained. It is established that with increasing loads from the wheel to the rail from 100 to 200 kN, the voltage on average increases by 50%. The stress distribution is affected by the rigidity of the elastic layer. When it increases, the vertical stresses in the sub-rail support decrease nonlinearly, while in traveling concrete they increase nonlinearly.

The Damage Deterioration Mechanism of Tunnel Structure under the Effect of Thermo-Mechanical Coupling and Its Maintenance

“…During the construction and operation of the deep-buried long big tunnels, the thermal and mechanical physical fields are combined significantly [16][17][18][19][20][21][22]. Under the impact of large temperature difference of "hot inside and cold outside", high-gradient temperature field would appear in the tunnel, which can cause serious deformation to lining concrete of the tunnel support structure, and it might damage the tunnel structure in severer cases [23][24][25][26]. At the same time, the surrounding rock of the tunnel support structure is subjected to high stress, which can lead to phenomena as such as cracking, hydraulic cracking, and instability, bringing threats to the safe operation of the tunnel.…”