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季节性冻土地区黄土隧道稳定性受较多因素影响,为了研究含水量变化和冻融循环次数对黄土隧道围岩变形规律的影响,以山西阳曲1号隧道为研究对象,对不同含水量黄土隧道进行多次冻融循环后的围岩变形规律进行研究。结果表明,含水量不变时,位移拱底最大,水平次之,拱顶最小;含水量增加时,水平、竖向位移迅速增加。冻融循环次数增加时,围岩水平位移、竖向位移都增加,产生较大变形,含水量越大,这种影响也越大。围岩在相同冻融循环情况下,拱底竖向位移最大,其次为拱顶竖向位移,拱腰处水平位移最小。随着围岩经历冻融循环次数的增加,水平位移、竖向位移都增加,产生较大变形,对围岩整体稳定性产生较大影响。随着冻融循环次数的增加,拱顶竖向位移、拱底竖向位移增长速率大于边墙水平位移,在拱顶拱底产生较大变形。
In order to study the influence of water content and the number of freeze-thaw cycles on the deformation of surrounding rock in loess tunnel, the stability of loess tunnel in seasonal frozen soil is influenced by many factors. Taking Yangqu No. 1 tunnel in Shanxi as the research object, The deformation of surrounding rock after several freeze-thaw cycles in loess tunnel is studied. The results show that when the water content is constant, the displacement arch bottom is the largest, the horizontal is the second, and the vault is the smallest. When the water content increases, the horizontal and vertical displacements increase rapidly. When the number of freeze-thaw cycles increases, the horizontal and vertical displacements of the surrounding rock increase, resulting in large deformations. The greater the water content, the greater this effect. Under the same freeze-thaw cycles, the vertical displacement of the arch bottom is the largest, followed by the vertical displacement of the dome, and the horizontal displacement of the arch waist is the smallest. As the surrounding rock undergoes an increase in the number of freeze-thaw cycles, the horizontal and vertical displacements all increase, resulting in large deformations that have a large impact on the overall stability of the surrounding rock. With the increase of the number of freeze-thaw cycles, the vertical displacement of the vault and the vertical displacement of the bottom of the arch increase faster than the horizontal displacement of the side wall, resulting in large deformation in the arch bottom.