Influence zones for 2D pile-soil-tunnelling interaction based on model test and numerical analysis

In the congested urban areas, tunnelling close to existing structures or services often occurs due to the lack of surface space. Consequently, tunnelling-induced ground movements may cause a serious damage to the adjacent structures. This study focussed on two-dimensional laboratory model test for the pile-soil-tunnelling interaction using a close range photogrammetric technique and numerical analysis. Model testing equipments and procedures were introduced, particularly the use of aluminium rods regarded as the frictional granular material. The normalised pile tip movements were identified by both the model test and finite element analysis. The model test results found to be in good agreement with the finite element analysis. Based on the normalised pile tip settlements due to tunnelling adjacent to a line of loaded piles, influence zones were proposed in this study. The proposed influence zones are relatively wider and deeper than those proposed in previous studies. The authors believe that it will be useful to decide the reasonable location of tunnel construction in the planning stage.