Bridge-tunnel transition section continuously welded rail track stability analysis method under extreme temperature condition

Abstract

The invention discloses an analysis method of bridge-tunnel transition section continuously welded rail track stability under an extreme temperature condition. The method comprises the following steps: (1) establishing a bridge-tunnel transition section continuously welded rail track complete model, wherein steel rails, sleepers and bridges are simulated through the adoption of beam units, fastener longitudinal-horizontal resistance and railway ballast longitudinal-horizontal resistance are simulated through the adoption of nonlinear springs, pier top anti-pushing rigidity is simulated through the adoption of a linear spring, a roadbed packing layer and the tunnel part are simulated through the adoption of entity units; (2) applying initial bending on a track structure through the whole model buckling mode analysis; (3) applying longitudinal nonlinear temperature load on the model aiming at an extreme temperature feature so as to research the horizontal deformation rule of the bridge-tunnel transition section continuously welded rail track. In fully consideration of nonlinear interaction among various structures, the initial defect is applied to the model based on the buckling mode, the analysis result is more suitable for the actual condition, and an important method for analyzing the stability of the continuously welded rail track under the extreme temperature condition is provided.

Description

technical field [0001] The invention relates to a seamless track stability analysis technology, in particular to a seamless track stability analysis method for a bridge-tunnel transition section under extreme temperature conditions. Background technique [0002] At present, areas with extreme temperature conditions such as Qinghai-Tibet and Heilongjiang often use ballasted track seamless lines. When the line passes through complex terrain and geological areas, bridges and tunnels are often connected by ultra-short foundations, and the seamless line-bridge-subgrade-tunnel forms a unified whole. In the case of cold wave, continuous high temperature, and large temperature difference between day and night, the steel rail bears a huge axial force. On the one hand, the bridge undergoes expansion and contraction deformation under the action of temperature, causing a nonlinear interaction between the bridge and the track. On the other hand, within a certain range inside and outsid...

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Problems solved by technology

[0004] At present, when conducting stability analysis of seamless lines, the unified stability calculation formula suggested by the code is often used, but the influence of bridge structural deformation cannot be considered; when conducting stability analysis of seamless lines on bridges, hypothetical steel rails are often used The initial bending obeys the trigonometric function distribution, and the initial defects of the rail are simulated by modifying the initial coordinates of the rail

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