Analysis of Stability and Determination of Tunnel Maintenance System by Discrete Element Method and Comparison of Its Case Results with Finite Difference Method (Case Study: Pardis Tunnel)

In recent years, the need for an accurate identification of the conditions of the earth has become apparent, in response to the growing need for larger and more deep underground spaces., underground excavations can be classified into three groups of tunnels, caverns and mines. The new township tunnels of the Pardis are part of the Phase 5, 8.9, and 11 new Pardis projects, which aim at providing access to these phases independently to the highway and the large Pardis of Tehran, and the arterial axis of the first phase of the 3.2 phase 1 and 4 new Pardis cities. The purpose of this research is to use different numerical methods for studying and analyzing the stability of Pardis tunnels in Karaj Formation using numerical methods of finite difference in continuous environment (FLAC software) and separate element in the discontinuous environment (UDEC software). In this research, the sustainability analysis of the tunnels of the Pardis was first performed and optimized by applying a variety of numerical methods. Finally, the results of different methods were compared with the results of the instrumentation. The results show that the model made by UDEC software is closer to real Earth conditions compared to the FLAC software. According to the results obtained from the comparison of the amount of displacement occurring around the drilled space, this environment has a discontinuous behavior.