Abstract In this paper, to explore the influence of mudstone rheological effect on the long-term stress deformation law of tunnel structures, the Burgers model is used for rheological numerical calculation. The calculation results are compared and discussed with long-term monitoring data of tunnels in similar situations at home and abroad to verify its rationality and correctness. The results show that under the rheological effect, the surrounding rock shows a trend of overall inward "flow" deformation during operation stage, the base uplift is the most obvious, and the deformation of the invert presents a "jujube pit" shape with a large middle and two small ends. The displacement of the invert and the filling layer shows an increasing trend over time, and remains basically stable after 50 years. The filling layer is in a tensile state, and the maximum principal stress in each part continues to increase over time, reaching a peak at 1/4 of the tunnel diameter away from the arch floor, and approaching the tensile strength of C25 concrete. In the practical project, the characteristics of invert floor heave are characterized by long time effect and difficulty in convergence. Therefore, when designing and constructing tunnels in mudstone, it is necessary to consider their rheological characteristics and their impact on the long-term deformation and stress of the tunnel structure.
Abstract：
In this paper, to explore the influence of mudstone rheological effect on the long-term stress deformation law of tunnel structures, the Burgers model is used for rheological numerical calculation. The calculation results are compared and discussed with long-term monitoring data of tunnels in similar situations at home and abroad to verify its rationality and correctness. The results show that under the rheological effect, the surrounding rock shows a trend of overall inward "flow" deformation during operation stage, the base uplift is the most obvious, and the deformation of the invert presents a "jujube pit" shape with a large middle and two small ends. The displacement of the invert and the filling layer shows an increasing trend over time, and remains basically stable after 50 years. The filling layer is in a tensile state, and the maximum principal stress in each part continues to increase over time, reaching a peak at 1/4 of the tunnel diameter away from the arch floor, and approaching the tensile strength of C25 concrete. In the practical project, the characteristics of invert floor heave are characterized by long time effect and difficulty in convergence. Therefore, when designing and constructing tunnels in mudstone, it is necessary to consider their rheological characteristics and their impact on the long-term deformation and stress of the tunnel structure.
2023, Vol. 60 