隧道湿软地基奥法施工英文版.doc

World Tunnel Congress 2008 - Underground Facilities for Better Environment and Safety - India Construction of mined tunnel in soft ground with NATM in Pirpanjal tunnel VA (KM. 152.600 – KM. 158.730) S.D. Jeur M. Gupta Hindustan Construction Co.Ltd, Mumbai, India SYNOPSIS: The case study explains the methodology and the state of art technology that was adopted in the construction of the first 650m from the South end of the Pirpanjal Tunnel Project in soft ground that consisted primarily of silty clay with boulder infested patches. The case study also reflects on the integral techniques of the NATM and how the same was utilized to suit the project requirement. It further goes on to describe the modifications to the general methodology that has to be incorporated due to the presence of fairly populated village above the alignment of the tunnel with very low overburden (20 – 40m). The job required involvement of various specialized machineries. The machineries were also been detailed hereunder with their specialty. 1. INTRODUCTION The existence of the only lifeline of transportation NH-1A connecting the planes of Jammu with the Kashmir valley has always being a point of concern. Frequent land slides and blockages in the snow bound winter times always demanded an alternative. Adding to the same, the matter that Railway network has not till date been established in this important state of ever developing India has always bothered the think tanks of Indian development. Drawing a solution, resolving the two-fold concern Northern Railways released their master plan to extend the railway service beyond Udhampur to Baramulla via Srinagar. IRCON International Limited took up the job for construction of the project from Laole to Quazigund and subletted the work of construction of the T-80 Tunnel extending from Ch. 152.600 to Ch. 163.560 to Hindustan Construction Co. Ltd. The contract work included excavation work with full support system for 10.350 km permanent concrete linin