Construction of the underground ventilation station while shield machines pass 1.5 m underneath

The project described in this paper is the construction of the Nakaochiai ventilation station on the Metropolitan Expressway Central Circular Shinjuku Route, using an open-cut construction method. Since the expressway mainline tunnel shields (mud-pressure shield) pass 1.5 m directly under the base slab, the face pressure of the shield charges to the base slab. Moreover, when the shield machines pass through the continuous retaining walls at the both ends of the ventilation station, ground water may flow into the open-cut area and the ground water pressure may lift up the base slab. To minimize the impact of the face pressure, underground water level is lowered both inside and outside the continuous retaining walls, so that the face pressure of the shield is minimized. In addition, the base slab and the retaining walls are connected and extra weight is set on the base slab to resist the uplift force by the face pressure. To lower the ground water table outside the retaining walls, the new approach of combination of chemical grouting and deep wells is developed. This paper introduces these countermeasures for shield passing and results of instrumentation measurements obtained during construction. (A) This paper was presented at Safety in the underground space - Proceedings of the ITA-AITES 2006 World Tunnel Congress and the 32nd ITA General Assembly, Seoul, Korea, 22-27 April 2006. For the covering abstract see ITRD E129148. "Reprinted with permission from Elsevier".

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/08867798
• Authors:
  • INOSE, K
  • KAMEGAYA, I
  • UEDA, A
  • IMANAKA, Y
• Publication Date: 2006-5

Language

• English

Media Info

• Pagination: 335-6
• Monograph Title: Rock chain 1: A set of codes for the studies of blocks instability inside a tunnel
• Serial:
  • Tunnelling and Underground Space Technology
  • Volume: 21
  • Issue Number: 3-4
  • Publisher: Elsevier
  • ISSN: 0886-7798
  • Serial URL: https://www.sciencedirect.com/journal/tunnelling-and-underground-space-technology

Subject/Index Terms

• TRT Terms: Construction; Evaluation; Measurement; Slabs; Tunnels
• Geographic Terms: Japan
• ITRD Terms: 3655: Construction; 9020: Evaluation (assessment); 8053: Japan; 6136: Measurement; 3491: Slab; 3374: Tunnel
• Subject Areas: Bridges and other structures; Construction; I54: Construction of Tunnels;

Filing Info

• Accession Number: 01032496
• Record Type: Publication
• Source Agency: Transport Research Laboratory
• Files: ITRD
• Created Date: Sep 6 2006 1:53PM