Each high cut face on the approach to the Terrace tunnel has been retained with a tied-back retaining wall anchored to an anchor drive with high strength alloy steel bars protected against corrosion. No standard analysis method was found for tied-back retaining walls or a final answer to the seismic forces involved. In the method used, the anchor bars are stressed to loads such that the principal stresses in the retained material, obtained by the use of a finite element method, do not imply a failure condition under a pseudo-static earthquake coefficient of 0.20. A limit equilibrium analysis using trial wedges was then used to find the seismic coefficient at which the ultimate tensile force in the bar would be reached. The design criteria required that the seismic coefficient be greater than 0.25. Details of the tied-back walls are outlined, the alternative methods considered are described and the design methods investigated are reviewed. The states of stress behind a wall, the limiting equilbrium analysis, the finite element analysis, and seismic loading are briefly discussed. The design of the reinforced concrete wall slab is outlined. The effective stress soil strength parameters and soil electric parameters are described and the anchor bar system is detailed. The anchor drive and wall finishes are also described.

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  • Corporate Authors:

    Technical Publications Limited

    C.P.O. 3047
    Wellington,   New Zealand 
  • Authors:
  • Publication Date: 1975-8-15

Media Info

  • Features: Figures; References; Tables;
  • Pagination: p. 242-247
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00128559
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Mar 10 1976 12:00AM