Experimental study of the crossing phases of a tunnel with the aid of a bidimensional model

The main purpose of this experimental and numerical work is to simulate the movements of the soil occurring during the construction of a shallow tunnel in a granular soil, and especially the phases of deconfining and reconfining due to the boring of a tunnel corresponding to the real phases of the construction work. The experimental device used is a small-scale two-dimensional model of a tunnel bored in the analogue soil of Taylor-Schneebeli soil consisting of metallic rods. The analysis of the tests is carried out using the numerical imagery which allows visualization of the complete displacement field in the soil mass obtained during the tests. The influence of the tunnel depth on the width of the surface depression and on the maximum surface settlement is presented.