Location
Arlington, Virginia
Date
15 Aug 2008, 11:00am - 12:30pm
Abstract
A broad gauge railway line is being constructed by Indian Railways in Himalaya. The total route length is 342kms, out of which about 100km is in tunnels. The tunnelling problem while excavating the Tunnel no.1 of Udhampur-Katra section and being faced currently is discussed in the paper. The D-shaped tunnel passes through thickly bedded, moderately soft, sparsely jointed sandstone, sheared claystones, siltstones and overburden comprising boulders/pebbles in sandy/silty matrix. The support pressure and the deformation were monitored to study the performance of the support system. Due to the presence of swelling minerals in claystone and weak & highly jointed rock formations with high rock cover (313m), the tunnel experienced both swelling and squeezing ground conditions resulting in the buckling of wall supports of steel ribs, cracking of tunnel wall concrete lining at places and floor heaving up to 1.2m. With the deformation of wall supports, the tunnel roof support also deformed. Numerical analysis using FLAC3D has been carried out to study the effectiveness of the support system. The study shows that the tunnel with out any support may have the wall deformations up to 2.76m. On the other hand, with rock bolt and 40cm thick steel fibre reinforced shotcrete (SFRS) support, the wall deformation would reduce to 23cm.
Department(s)
Civil, Architectural and Environmental Engineering
Meeting Name
6th Conference of the International Conference on Case Histories in Geotechnical Engineering
Publisher
Missouri University of Science and Technology
Document Version
Final Version
Rights
© 2008 Missouri University of Science and Technology, All rights reserved.
Creative Commons Licensing
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.
Document Type
Article - Conference proceedings
File Type
text
Language
English
Recommended Citation
Goel, R. K. and Swarup, Anil, "Case History of Tunnelling Through Claystone" (2008). International Conference on Case Histories in Geotechnical Engineering. 4.
https://scholarsmine.mst.edu/icchge/6icchge/session06/4
Case History of Tunnelling Through Claystone
Arlington, Virginia
A broad gauge railway line is being constructed by Indian Railways in Himalaya. The total route length is 342kms, out of which about 100km is in tunnels. The tunnelling problem while excavating the Tunnel no.1 of Udhampur-Katra section and being faced currently is discussed in the paper. The D-shaped tunnel passes through thickly bedded, moderately soft, sparsely jointed sandstone, sheared claystones, siltstones and overburden comprising boulders/pebbles in sandy/silty matrix. The support pressure and the deformation were monitored to study the performance of the support system. Due to the presence of swelling minerals in claystone and weak & highly jointed rock formations with high rock cover (313m), the tunnel experienced both swelling and squeezing ground conditions resulting in the buckling of wall supports of steel ribs, cracking of tunnel wall concrete lining at places and floor heaving up to 1.2m. With the deformation of wall supports, the tunnel roof support also deformed. Numerical analysis using FLAC3D has been carried out to study the effectiveness of the support system. The study shows that the tunnel with out any support may have the wall deformations up to 2.76m. On the other hand, with rock bolt and 40cm thick steel fibre reinforced shotcrete (SFRS) support, the wall deformation would reduce to 23cm.
