INDONESIAN MINING PROFESSIONALS JOURNAL
Vol 1, No 1 (2019): NOVEMBER

Stability Analysis of the Nanjung Water Diversion Twin Tunnels based on Convergence Measurement

Simon Heru Prassetyo (Teknik Pertambangan, Fakultas Teknik Pertambangan dan Perminyakan, Institut Teknologi Bandung, Bandung 40132)
Ganda Marihot Simangunsong (Teknik Pertambangan, Fakultas Teknik Pertambangan dan Perminyakan, Institut Teknologi Bandung, Bandung 40132)
Ridho Kresna Wattimena (Teknik Pertambangan, Fakultas Teknik Pertambangan dan Perminyakan, Institut Teknologi Bandung, Bandung 40132)
Made Astawa Rai (Teknik Pertambangan, Fakultas Teknik Pertambangan dan Perminyakan, Institut Teknologi Bandung, Bandung 40132)
Irwandy Arif (Teknik Pertambangan, Fakultas Teknik Pertambangan dan Perminyakan, Institut Teknologi Bandung, Bandung 40132)
Nuhindro Priagung Widodo (Teknik Pertambangan, Fakultas Teknik Pertambangan dan Perminyakan, Institut Teknologi Bandung, Bandung 40132)
Dhika Noor Pradhana (PT. Wijaya Karya (Persero) Tbk, Proyek Pembangunan Terowongan Nanjung, Kabupaten Bandung)
Dimas Agung Saputra (PT. Wijaya Karya (Persero) Tbk, Proyek Pembangunan Terowongan Nanjung, Kabupaten Bandung)



Article Info

Publish Date
17 Dec 2019

Abstract

This paper focuses on the stability analysis of the Nanjung Water Diversion Twin Tunnels using convergence measurement. The Nanjung Tunnel is horseshoe-shaped in cross-section, 10.2 m x 9.2 m in dimension, and 230 m in length. The location of the tunnel is in Curug Jompong, Margaasih Subdistrict, Bandung. Convergence monitoring was done for 144 days between February 18 and July 11, 2019. The results of the convergence measurement were recorded and plotted into the curves of convergence vs. day and convergence vs. distance from tunnel face. From these plots, the continuity of the convergence and the convergence rate in the tunnel roof and wall were then analyzed. The convergence rates from each tunnel were also compared to empirical values to determine the level of tunnel stability. In general, the trend of convergence rate shows that the Nanjung Tunnel is stable without any indication of instability. Although there was a spike in the convergence rate at several STA in the measured span, that spike was not replicated by the convergence rate in the other measured spans and it was not continuous. The stability of the Nanjung Tunnel is also confirmed from the critical strain analysis, in which most of the STA measured have strain magnitudes located below the critical strain line and are less than 1%.

Copyrights © 2019






Journal Info

Abbrev

impj

Publisher

Subject

Aerospace Engineering

Description

This Journal is published periodically two times annually : April and October, containing papers of research and development for mineral and coal, including Mining Exploration, Surface Mine System and Operation, Underground Mine System and Operation, Geotechnical, Mine Safety and Mine Environment, ...