MECHANICS OF PIPING IN COHESIVE SOILS

A REVIEW OF PIPING MECHANISM AND FILTER REQUIREMENTS OF COHESIVE SOILS IS GIVEN. THE EXPERIMENTAL SETUP USED, TYPE OF SOIL TESTED, AND THE OBSERVATIONS REPORTED BY VARIOUS INVESTIGATORS ARE CRITICALLY REVIEWED. THE FIELD OBSERVATIONS OF VARIOUS INVESTIGATORS ARE SUMMARIZED. FLOW CONDITIONS OF SEEPING WATER THROUGH A BASE SOIL SITUATED ABOVE A FILTER OPENING ARE ANALYZED BY MEANS OF A FLOW NET. BASED ON THE EXPERIMENTAL OBSERVATIONS OF PREVIOUS INVESTIGATIONS AND THE SOIL STRUCTURE OF COMPACTED BASE SOIL, TWO DISTINCT TYPES OF FAILURE ARE PROPOSED, ONE BASED ON PLASTIC FAILURE MECHANISM AND THE OTHER BASED ON THE BRITTLE FAILURE MECHANISM. THE SOILS COMPACTED ON THE WET SIDE OF OPTIMUM AND SEDIMENTED AND CONSOLIDATED SAMPLES MAY BE CHARACTERIZED TO FAIL BY THE PLASTIC FAILURE MECHANISM. FOR THIS TYPE OF FAILURE TWO EXPRESSIONS ARE PROPOSED FOR CRITICAL EXIT GRADIENT: ONE BASED ON MOHR-COULOMB YIELD CRITERIA AND THE OTHER BASED ON VON MISES YIELD CRITERIA. THE SOILS COMPACTED ON THE DRY SIDE OF OPTIMUM MAY BE CHARACTERIZED TO FAIL BY BRITTLE FAILURE MECHANISM. FOR BRITTLE TYPE OF FAILURE TWO EXPRESSIONS ARE PROPOSED FOR CRITICAL EXIT GRADIENT, ONE BASED ON GRIFFITH-BRACE CRITERIA AND ANOTHER BASED ON GRIFFITH-MURREL CRITERIA. A COMPREHENSIVE EXPERIMENTAL PROGRAM IS ENVISAGED TO STUDY THE PIPING MECHANISM IN COHESIVE SOILS AND TO VERIFY THE PROPOSED METHODS FOR THE DETERMINATION OF CRITICAL EXIT GRADIENT. THE VARIOUS FACTORS TO BE CONSIDERED IN THE INVESTIGATION ARE LISTED. /AUTHOR/

  • Corporate Authors:

    College of Engineering, Madras /India

    ,    
  • Authors:
    • Kulandaiswamy, V C
    • Sakthivadivel, R
    • Thanikachalam, V
  • Publication Date: 1971-10

Media Info

  • Features: Figures; References; Tables;
  • Pagination: 100 p.
  • Serial:
    • Issue Number: 6

Subject/Index Terms

Filing Info

  • Accession Number: 00238061
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Aug 31 1972 12:00AM