A NUMERICAL APPROACH TO ESTIMATING THE HEIGHT AND THE WIDTH OF THE COLLAPSE ZONE AROUND HORSESHOE TUNNEL

• Main Author: Danava, Deo
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/75928
• Institution: Institut Teknologi Bandung

Tunnels are one of the most essential infrastructures either for civil or mining construction. The most critical challenge in planning and building tunnels is ensuring the stability of the structure from the loads received by the surrounding rock masses. The tunnel stability analysis closely relates to the arching phenomenon or the arch effect. In the context of tunnels, arching refers to forming an arch that encloses the area around the tunnel due to the stress redistribution from the surrounding rock. The arch covering this area is considered to be an unstable area or known as a collapse zone. However, the understanding and use of the method in determining the shape of the collapse zone still need to be improved in depth. This study attempts to provide a new approach by using numerical methods to determine the collapse zone around tunnels. Using data from two case studies, namely the Piaoli highway tunnel in China and the Notog railway tunnel in Indonesia, researchers attempted to analyze and determine the effect of stress distribution on the formation of the height and width of the collapse zone. Using the data from the two case studies, the researcher can perform simulations to observe different types of stress distribution around the tunnel. Observation of various types of stress distribution will provide new insights into observing and determining the shape of the collapse zone. The analysis results indicate that the height and width of the collapse zone around the horseshoe section tunnel can be determined by observing the behavior of the vertical stress and the mean stress distribution