MAINTENANCE OF SNCF UNDERGROUND STRUCTURES. THE BLAISY BAS TUNNEL

ENTRETIEN DES OUVRAGES SOUTERRAINS SNCF TUNNEL DE BLAISY BAS

Problems of stability arose in a tunnel along a heavily trafficked railway line, which had to be kept open to traffic during maintenance operations. The tunnel is built through marl, limestone, sandstone and dolomite. The drilling operations led to a modification in natural hydrogeology causing important movements of water in a terrain in which they did not occur before the construction of the tunnel. These movements were the cause of disorders. Strengthening of the line was carried out in 1922 and 1973. In 1973, two methods were used: (1) strengthening of the rock with bentonite-cement injection, and (2) installation of a dense network of cast-in-situ micro-piles. The first technique was used to fill pockets under the footing, thus improving the bearing capacity; the second formed a thick layer which replaced the shallow foundation. /TRRL/

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  • Corporate Authors:

    Editions Sovim

    8 rue Jean-Claude Vivant 61-63
    Paris,   France 
  • Authors:
    • Chavignaud, J P
  • Publication Date: 1974-5-6

Language

  • French

Media Info

  • Features: Figures; Photos; Tables;
  • Pagination: p. 135-145
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00137700
  • Record Type: Publication
  • Source Agency: Central Laboratory of Bridges & Highways, France
  • Files: ITRD, TRIS
  • Created Date: Nov 17 1976 12:00AM