EXCAVATION IN COHESIVE SOILS: MODELLING THE EFFECTS OF CREEP ON LONG-TERM PERFORMANCE. NUMERICAL MODELS IN GEOMECHANICS. NUMOG III. PROCEEDINGS OF THE 3RD INTERNATIONAL SYMPOSIUM HELD IN NIAGARA FALLS, CANADA, 8-11 MAY 1989

This paper presents a numerical procedure for simulating excavation in cohesive soils incorporating time-dependent creep effects. The techniques presented are based on a recently developed excavation analysis algorithm proposed by borja, lee and seed (1988) that captures the uniqueness of the solution irrespective of the sequence of excavation for both elastic and elastoplastic materials. This algorithm provides a theoretically correct and analytically efficient solution to the basic problem of nonlinear elasto-plastic modelling of incremental excavation. An extended three-dimensional cam-clay plasticity model which includes modelling of time-dependent creep effects is employed to characterize the constitutive behavior of the elasto-plastic material. Stress integration is performed implicitly and a consistent tangent operator is evaluated to guarantee rapid convergence of an iterative solution to the resulting nonlinear equations based on the Newton-Raphson scheme. The algorithm and the constitutive model are then applied to the analyses of a series of excavations in Boston blue clay in connection with the construction of an underground post office square garage structure in Boston, massachusetts.(a) for the covering abstract of this conference see IRRD 824029.

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    Elsevier Science Publishers

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  • Authors:
    • Borja, R I
    • LEE, S R
    • Seed, Raymond B
  • Publication Date: 1989

Language

  • English

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  • Accession Number: 00497965
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • ISBN: 1-85166-425-4
  • Files: ITRD, TRIS
  • Created Date: Sep 30 1990 12:00AM