STABILITY ANALYSIS OF THE NOTOG DOUBLE-TRACK RAILWAY TUNNEL BASED ON DISPLACEMENT MONITORING DATA

• Main Author: ELIZABET (NIM : 22117028), FIDELIS
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/27313
• Institution: Institut Teknologi Bandung

In designing the tunnels, stability of the tunnel becomes crucial. The stability of tunnel is affected by rock conditions around the tunnel. As complexity and unpredictability exist in nature, careful observations and interpretations of what can be measured in the field become prerequisites for geomechanical engineers to conduct safe tunnel construction works. This research is conducted in double-track railway tunnel of Notog located in Central Java, Indonesia. Total Station is used for measuring the tunnel deformation performed at section 395 STA. Based on the monitoring data, rock mass parameters is then determined by trial and error back analysis. Monitoring data at points A, B, and C installed at the tunnel perimeter, tunnel deformation is obtained (in the form of displacement of monitoring points) as follows, point A = 8.2 mm, point B = 3.8 mm, and point C = 1.7 mm. Numerical modeling using finite element method is used for tunnel stability analysis. Regarding to Factor of Safety (FoS) calculation, Mohr-Coloumb failure criterion is adopted and determined. Characteristic of material using back analysis by trial and error based on the data of deformation monitoring. The results show that Young's Modulus ( E ) from numerical modelling is predicted to vary from 25.5% to 56.53% of the laboratory tests, and the FoS of the tunnel with permanent support at point A, B, C, D, and E are 2.62, 2.20, 2.56, 2.45, and 2.68 respectively.