Buried pipeline-soil interaction caused by shield tunnelling based on a simple continuum model

Abstract

Two problems exist in the theoretical research on pipeline--soil interaction caused by tunnelling. First, it is difficult for the existing mathematical models to maintain both simplicity and accuracy; second, most studies focus on the vertical pipeline-soil interaction and ignore the horizontal pipeline deformation. Based on a continuum medium model, the pipeline-soil interaction caused by shield tunnelling was simulated to determine both the vertical and horizontal soil displacement fields. The governing equations for both the pipeline deformation function and attenuation function were constructed based on the variation principle. These two functions are coupled and then decoupled by an iterative process. The model has the following advantages: 1. The model has a simple solution form that is convenient for application. 2. The model includes the influence of soil continuity and produces results with a good precision. 3. The proposed model is able to calculate the analytical expression of the soil spring factor and soil shear stiffness factor, making it possible to quantitatively analyze the pipeline--soil interaction. Through comparison with monitoring data, the proposed method was verified. Ultimately, the parametric study shows that large horizontal pipeline deformation may be caused by shield tunnelling, and the influence of soil continuity on pipeline--soil interaction is remarkable.