城市地下管线受隧道施工影响的显式解分析

为研究地下管线受隧道施工的影响,基于Winkler弹性地基梁理论和相关研究成果,综合考虑隧道施工对地下管线的影响范围,对现有计算公式进行了修正,给出了单线隧道施工时地下管线变形的显式解,并提出了一种适用于求解地下管线转角、弯矩和剪力等力学响应的新方法。在此基础上,利用MATLAB计算软件对所提出的方法进行了验证性计算,论证了其可靠性。最后,利用叠加原理,进一步提出了双线平行隧道施工时地下管线力学响应的计算方法。研究表明:双线隧道施工下地下管线的力学响应与单线隧道存在显著差异,并且双线隧道间距对地下管线的力学响应存在显著影响:随双线隧道间距的变化,地下管线的变形和转角分布趋势基本不变,但最大变形和转角总比单线隧道大;然而,存在一定范围,当隧道间距在此范围外时,最大弯矩和剪力比单线隧道大,在此范围内时,最大弯矩和剪力会出现比单线隧道小的情况。文章为分析地下管线在单、双线隧道施工条件下的力学响应提供了一种有效的计算方法,可为保障城市地下管线的安全运行评估提供理论参考。

Explicit solution analysis of underground pipeline mechanical responses under tunnel construction conditions

To study the influence of tunnel construction on the behavior of underground pipelines, this paper presents a modification to the formula for calculating the pipeline deformation based on the Winkler elastic foundation beam theory and previous related results. We also give an explicit solution in single line tunnel case and a new method of solving for the mechanical responses such as the bending angle, bending moment and shear force of an underground pipeline. The method is verified through calculations using MATLAB. By the superposition principle, we derive a method for direct calculation of the mechanical responses of a pipeline subjected to the construction of twin tunnels in parallel. Results show that the responses of such a twin tunnel case are significantly different from those of the single line tunnel case, and that the spacing of twin tunnels is a major factor influencing the responses. When the spacing is varied, the distributions of deformation and bending angle of the pipeline are nearly the same, but the peak magnitudes are always larger than those of single line tunnel case. And there exists a certain range of the spacing, beyond which the peak bending moment and peak shear force are larger than those of single line case. Within this range, both appear smaller. This study provides an effective method for calculating the mechanical responses of underground pipelines to ground movement under construction of single and twin tunnels, thereby helping safety evaluation of urban underground pipeline operation.