水下隧道合理覆盖层厚度的有限元模拟研究

FEM adopted to determine the reasonable overburden thickness for a subaqueous tunnel

水下隧道覆盖层厚度目前基本上是凭经验确定的,采用不同的经验公式得到的计算结果差异很大。文章针对目前情况提出了采用有限元的求解方法,并结合公路隧道施工规范,模拟了拟建的重庆朝天门两江隧道在不同隧道覆盖层厚度时的拱顶位移和拉应力的分布及大小。通过与标准隧道的比较,得出了该隧道的合理覆盖层厚度,对同类工程有一定的参考价值。

At present, overburden thickness of a subaqueous tunnel is in general determined by experience, which leads to diversified results as obtained by different empirical formulae. In this context, authors of the paper, considering the Highway Tunnel Construction Code, adopted FEM to compute the crown displacements and principal tensile stresses in arch crown under different overburden thicknesses of a subaqueous tunnel. Through comparison with a typical tunnel, the reasonable overburden thickness is obtained. The study is helpful for similar projects.