Endochronic Constitutive Law for Liquefaction of Sand.

Abstract

A nonlinear constitutive law is developed to describe the densification and hysteresis of sand under cyclic loading. This law, together with the previously estabished model for an inelastic two-phase medium, gives a realistic prediction of the pore pressure buildup and associated liquefaction of sand due to cyclic shear. The law is of the endochronic type and consists of quasi-linear first-order differential equations expressed in terms of intrinsic time, which is an independent variable whose increments depend on the strain increments. This accounts for the accumulation of particle rearrangements, which are characterized by a parameter termed the rearrangement measure. The basic extensions of this work with regard to the application of endochronic theory to metals are due to the fact that sands densify upon shearing and are sensitive to confining stress; these two features are shared with the formulation of endochronic theory for concrete. Several typical examples are given to illustrate the ability of the developed theory to adequately characterize the densification, hysteresis, and liquefaction tendency of sands subjected to cyclic shear in laboratory tests. (Author)

Document Details

Document Type
Technical Report
Publication Date
Aug 01, 1976
Accession Number
ADA029937

Entities

People

  • Raymond J. Krizek
  • Zdeněk Bažant

Organizations

  • Northwestern University

Tags

DTIC Thesaurus Topics

  • Buildings And Structures
  • Concrete
  • Differential Equations
  • Equations
  • Hysteresis
  • Laboratory Procedures
  • Laboratory Tests
  • Materials Laboratories
  • Particles
  • Pore Pressure
  • Research Facilities

Readers

  • Adaptive Control and Estimation with Uncertainty in Dynamic Systems.
  • Geotechnical Engineering.
  • Materials Science and Engineering.