Evaluation of Sample Disturbance on Soils Using the Concept of 'Reference Strain'.
Abstract
Reference strain is a shear strain value that is obtained by dividing the shear strength by the initial tangent shear modulus. On a shear stress versus shear strain plot, it can be thought of as the shear strain at which the initial tangent shear modulus line, if extended, intersects the horizontal line through the point of maximum shear stress. If each shear strain value of a shear stress versus shear strain curve is divided by the reference strain and if each shear stress value is divided by the maximum shear stress, a normalized stress curve is obtained. Results of torsional simple shear tests and of triaxial compression tests give essentially the same normalized shear stress versus normalized shear strain curve. Use of reference strain provides normalized stress-strain curves which are independent of sample disturbance. These normalized curves may be used to establish in situ stress-strain behavior by making use of initial tangent shear moduli obtained in the field from seismic tests and by using undrained shear strengths (only needed for undrained field loading conditions) obtained by conventional field tests. This procedure utilizes the 'sense' of the soil behavior from the normalized laboratory curve, and the 'magnitude' of the behavior is obtained from field measurements. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1979
- Accession Number
- ADA077913
Entities
People
- Vincent P. Drnevich
Organizations
- University of Kentucky