Accession Number:

ADA250896

Title:

Crack Propagation and Fabric Control on the Static and Dynamic Strength of Cohesive Soils

Descriptive Note:

Final rept. 1 Jun 1988-31 Jan 1992,

Corporate Author:

CASE WESTERN RESERVE UNIV CLEVELAND OH

Personal Author(s):

Report Date:

1992-01-31

Pagination or Media Count:

326.0

Abstract:

Discontinuities in the form cracks or fissures and inclusions are often present in natural clays. They serve as stress concentrators when loads are applied to the material. Such concentrations result in the cracks advancing, often surrounded and preceded by a propagating damage zone. As the crack propagates, the damage may be in the form of one or more shear bands, which may play the part of new stress concentrators and blunt the action of the original crack. This report examines some of the phenomena associated with the presence of cracks in overconsolidated clays as well as in the less brittle normally consolidated clays. Differences between isotropic and anisotropic materials, and the level at which serious modifications take place in the fabric of the material are noted. Observations made with a surface analyzer as well as with a transmission electron microscope indicate that the changes in fabric mostly occur at the level of the cluster or flock. The influence of the cracks and of the shear bands on the kinematics and strength of the test specimens is studied and discussed.

Subject Categories:

  • Soil Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE