Numerical Analysis for Elucidating the Effect of Tunnel Excavation in Gravel-Mixed Ground

In tunnel construction in gravel-mixed ground, it is extremely important to predict the risk of gravel dropout and the accompanying large deformation of the substrate ground. The distribution and shape of gravel vary, and it is difficult to reproduce the situation depending on the individual site. Therefore, in this study, we created a model of the gravel-mixed ground using the Voronoi partition model. Then, by mathematical analysis, the gravel shape that appears in the actual phenomenon could be reproduced in consideration of randomness and inhomogeneity. In addition, it was clarified that the gravel extrusion phenomenon and the large deformation of the ground can be expressed.