Static Stress-Deformation Characteristics of Sand

Citation

Ko, Hon-Yim (1966) Static Stress-Deformation Characteristics of Sand. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/WWZB-SM07. https://resolver.caltech.edu/CaltechETD:etd-09252002-133202

Abstract

NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in.pdf document. A soil test box, capable of applying any combination of principal stresses to a cubical soil sample, was developed for the experimental investigation of the behavior of granular soils under static loading. A stress control device was also developed, enabling a continuous and proportionate change to be made in the stresses along a stress path and considerably simplifying the calculation of the stress state in the sample. The apparatus was used to investigate (a) the hydrostatic compression of an Ottawa sand, and (b) the behavior of the same soil under various deviatoric stress paths in both loading and unloading conditions. A theoretical "holey" model was postulated for sand under hydrostatic stress and the results of the analysis of this model were found to correlate closely with the experimental data. The qualitative behavior of sand under shear stresses was examined from a particulate point of view. Specially designed tests were performed on the Ottawa sand with loading and unloading along stress paths which involved different combinations of hydrostatic and deviatoric stresses, with the purpose of examining the proportions of recoverable and irrecoverable deformations. A failure envelope was obtained for a medium dense and a medium loose sand by monotonically increasing [...] while keeping [...] constant under various conditions of stress distribution, and it was found that the value of equivalent Coulomb [...] increased from 42? in triaxial compression to 48? in triaxial extension for the medium dense sand and from 36? in triaxial compression to 44? in triaxial extension for the medium loose sand.

Thesis Files