Ground characterization and comparative analysis of ground response to conventional and mechanized tunneling in Lahore, Pakistan | |
| Author | Danish, Muhammad |
| Call Number | AIT Thesis no.GE-16-06 |
| Subject(s) | Engineering geotechnical. Tunnel lining. Geology. Geology--Pakistan. |
| Note | A thesis submitted in partial fulfillment of the requirements for the d egree of Master of Engineering in Geotechnical and Earth Resources Engineering |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. GE-16-06 |
| Abstract | Tunnelling in metropolitan territories , frequently founded on soft alluvial deposits , is a standout amongst the most difficult callings in all disciplines of geotechnical engineering. Soft ground tunnels may have deplorable aftermaths and incite extensive movements in surrounding ground if not built conforming to prevailing conditions. This study is focused on tunnelman’s characterization of Quaternary alluv ial deposits in district Lahore of Pakistan and comparative numerical asse s sment of ground response to conventional and mechanized tunnelling methods along route of under construction Orange Line Metro Train (OLMT) Project. Tunnelman’s classification criteria ( Terzaghi, 1950 followed by Huer, 1974 ) has been employed to infer the likely ground behavior & potential hazards in response to tunnelling invoked distress along five distinct alignments spread across Lahore metropolitan . Ground conditions along these profiles are likely to depict wide range of behavior including firm & stable, coh esive running, slow to fast rav e ling, running, flowing and slow creeping followed by plastic shear failure in worst cases, contingent to soil type and relative position with respect to ground water table . A series of plane strain numerical analyses has been performed thereafter for comparative evaluation of ground behavior in response to various face advance schemes of conventional tunnelling method and mechanized excavation. Numerous cases of single and twin tunnels ’ construction , with two distinct cover depths and with & without ring of improved ground around opening, have been analyzed. For conventional method , d ouble sidewall drift pattern (DSD - I) has been discovered most optimum in all cases being associated with least potential of provoking dis ruption in encompassing ground mass . Extent of ground deformation depletes further with shell of improved ground around opening and with increased shotcrete stiffness . For mechanized tunnelling , restricting volume loss to least possible value is desirable to restrain ground movements . Construction of twin tunnels is found more promising, compared to single large tunnel , being associated with small excavation damaged zone s (EDZ) attributed to their small size s . Lining forces vary with method of tunnel construction employed with maximum values , in general, for the method associated with least ground deformations . These outcomes may pave out solutions to numerous issues of upcoming projects of similar nature in comparable geological setups |
| Year | 2017 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. GE-16-06 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Geotechnical Engineering (GE) |
| Chairperson(s) | Noppadol Phien - Wej; |
| Examination Committee(s) | Chao, Kuo-Chieh;Pham, Huy Giao; |
| Scholarship Donor(s) | Thailand (HM King); |
| Degree | Thesis (M. Eng.) - Asian Institute of Technology, 2017 |