Numerical analysis by comparing the Drucker-Prager and Mohr-Coulomb behaviors to optimize the best sites for constructing a new tunnel adjacent to the old one

Abstract

The tunnels are one of the most significant infrastructures for facilitating mobility in mountainous terrain. It has several benefits, including shortening distances, time, and ease of transportation. To make it easier, developed countries create several tunnels close to each other. Engineers face the necessity of building these new tunnels near existing ones; this infrastructure must be safe. In this paper, for this numerical study, we used the OptumG2 software to analyze the position of a new tunnel created in six locations: bottom, top, left (two places at 12 m and 32 m), and right (two places at 12 m and 32 m) by the finite element method. This study was analyzed using two criteria: the equivalent of Drucker Prager and Mohr Coulomb. We are interested in the total field of the displacement, the vertical displacement of the model, the displacement, bending moment, shear, and normal force of the concrete lining. The findings of this numerical analysis using the Drucker Prager and Mohr Coulomb behaviors to determine the ideal locations for building a new tunnel next to an existing one show that the new bottom tunnel might have a significant influence on the stability of the existing tunnel. It was also observed that the maximum displacement present when we add a new tunnel at the bottom meets the Drucker-Prager criteria.