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Type of Document	Dissertation
Author	Bell, James M.
URN	etd-03242003-102726
Persistent URL	http://resolver.caltech.edu/CaltechETD:etd-03242003-102726
Title	Stress-strain characteristics of cohesionless granular materials subjected to statically applied homogenous loads in an open system
Degree	PhD
Option	Engineering and Applied Science
Advisory Committee	Advisor Name Title Unknown Committee Member
Keywords	None
Date of Defense	1964-09-01
Availability	unrestricted
Abstract A general stress-strain relationship in incremental and invariant form is derived for sand on the basis of experimental evidence. The resulting expression does not include the yield condition but makes allowance for the direction of loading and the state of stress. Two new modified and dimensionless invariant functions are introduced and a detailed description and classification of stress paths presented. A new first yield criterion for sand stressed to yield along one stress path is developed from experimental evidence. The friction angle in triaxial compression was minimum and 14[degrees] less than that in triaxial extension. The Mohr-Coulomb yield criterion extended to three dimensions is rejected. Emphasis is placed on the importance of obtaining homogeneous stress in physical experiments. A new spherical compression apparatus was developed to study the behavior of sand under spherical compression. Disadvantages of former apparatuses were largely overcome by elimination of frictional loading, and a homogeneous state of stress was obtained. A new stress controlled three-dimensional compression apparatus capable of applying principal stresses to a rectangular, plate sample was developed to study the behavior of sand under a general stress state, particularly under deviatoric stress. This apparatus provided for the independent measurement of volumetric strain and allowed for the development of considerable deformation in obtaining yield.
Files	Filename       Size       Approximate Download Time (Hours:Minutes:Seconds)     28.8 Modem   56K Modem   ISDN (64 Kb)   ISDN (128 Kb)   Higher-speed Access    Bell_jm_1965.pdf 26.97 Mb 02:04:51 01:04:13 00:56:11 00:28:05 00:02:23