STRESSES AND STRAINS AROUND A CYLINDRICAL TUNNEL IN AN ELASTO-PLASTIC MATERIAL WITH DILATANCY

AN ELASTO-PLASTIC SOLUTION IS GIVEN FOR DETERMINING THE STRESSES, STRAINS, AND DISPLACEMENTS AROUND A CIRCULAR TUNNEL IN ROCK. THE RELATIONSHIP BETWEEN THE PRINCIPAL STRESSES IN THE PLASTIC ZONE ARE DETERMINED BY THE COULOMB-NAVIER FAILURE CRITERIA, AND THE CONCEPT OF "NORMALITY" IS USED TO RELATE THE PLASTIC STRAINS TO THE "YIELD" SURFACE. THE "NORMALITY" CONCEPT RESULTS IN A DILATANCY OF THE MATERIAL AT YIELDING WHEN THE ANGLE OF SHEARING RESITANCE OF THE MATERIAL IS GREATER THAN ZERO. THUS THE DISPLACEMENTS CALCULATED BY THE METHOD GIVEN IN THIS REPORT INCLUDE THE EFFECT OF DILATANCY IN THE YIELDED ZONE AROUND THE TUNNEL. THE RESULTS OF THE STUDY ARE PRESENTED IN GRAPHICAL FORM, WHICH ENABLE A WIDE VARIETY OF PROBLEMS TO BE SOLVED BY HAND WITHOUT THE USE OF A DIGITAL COMPUTER. THE METHOD OF ANALYSIS PRESENTED IS ESPECIALLY APPLICABLE TO PROBLEMS WHERE LOADS ARE IMPOSED AFTER THE LINER IS INSTALLED, AS IN THE CASE OF THE DESIGN OF PROTECTIVE STRUCTURES. THE METHOD GIVEN HEREIN IS USEFUL FOR DESIGN BECAUSE THE CALCULATION OF DEFORMATIONS AND STRAINS, RATHER THAN STRESSES, ENABLES THE DESIGNER TO DETERMINE IF A PARTICULAR TYPE OF LINER CAN TOLERATE THE DEFORMATIONS IMPOSED AT THE ROCK-LINER INTERFACE. SUGGESTIONS ARE ALSO GIVEN FOR THE SELECTION OF THE ROCK MASS PROPERTIES TO BE USED IN THE ANALYSIS; I.E., DEFORMATION MODULI AND SHEAR STRENGTH PROPERTIES. /AUTHOR/

  • Corporate Authors:

    U.S. Army Corps of Engineers

    ,    
  • Authors:
    • HENDRON, A J
    • Aiyer, A K
  • Publication Date: 1972-9

Media Info

  • Features: Figures; References;
  • Pagination: 83 p.
  • Serial:
    • Issue Number: 10

Subject/Index Terms

Filing Info

  • Accession Number: 00236450
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Apr 8 1973 12:00AM