Effects of oversized particles on the dynamic properties of sand specimens evaluated by resonant column testing
type: CreativeWork
description: This study was motivated by the fact that many times intact specimens with a number of oversized particles are dynamically tested in the laboratory and the impact of the particles on the dynamic properties is unknown. The effects of oversized particles represented by gravel particles on the shear modulus (G) and material damping ratio (D) of a uniform sand were evaluated in the linear (γ ≤ 0.001%) and nonlinear (γ > 0.001%) ranges of shear strain with combined resonant column and torsional shear (RCTS) equipment. The sand used in this investigation is a uniform sand as a reference, well-characterized material on the dynamic properties. Sand-gravel specimens were constructed using the undercompaction method. A variety of rounded gravel particles was used in building the specimens. Dynamic tests on the sand-gravel specimens were performed, and the tests results are presented. Among the findings of this investigation are that, compared to uniform sand: (1) oversized gravel particles symmetrically located along the longitudinal axis in uniform sand generally decreased slightly the small-strain shear modulus (Gmax), (2) oversized gravel particles asymmetrically located away from the longitudinal axis of rotation resulted in slight increases in Gmax and the small-strain material damping ratio (Dmin), (3) the G – log γ relationships of sand-gravel specimens with asymmetrically located gravel particles are generally above those with gravel particles symmetrically located along the longitudinal axis, and (4) the G/Gmax – log γ relationships of all specimens were reasonably close for the nonlinear ranges covered in these tests (γ < 0.05 % and G/Gmax > 0.6). As long as the oversized particles were near the axis of rotation, the particles had little effect on the dynamic properties (Gmax, Dmin and G – log γ relationships) regardless of sizes and numbers of particles. However, once the oversized particles were located away from the axis of rotation and closer to the perimeter of…
abstract: This study was motivated by the fact that many times intact specimens with a number of oversized particles are dynamically tested in the laboratory and the impact of the particles on the dynamic properties is unknown. The effects of oversized particles represented by gravel particles on the shear modulus (G) and material damping ratio (D) of a uniform sand were evaluated in the linear (γ ≤ 0.001%) and nonlinear (γ > 0.001%) ranges of shear strain with combined resonant column and torsional shear (RCTS) equipment. The sand used in this investigation is a uniform sand as a reference, well-characterized material on the dynamic properties. Sand-gravel specimens were constructed using the undercompaction method. A variety of rounded gravel particles was used in building the specimens. Dynamic tests on the sand-gravel specimens were performed, and the tests results are presented. Among the findings of this investigation are that, compared to uniform sand: (1) oversized gravel particles symmetrically located along the longitudinal axis in uniform sand generally decreased slightly the small-strain shear modulus (Gmax), (2) oversized gravel particles asymmetrically located away from the longitudinal axis of rotation resulted in slight increases in Gmax and the small-strain material damping ratio (Dmin), (3) the G – log γ relationships of sand-gravel specimens with asymmetrically located gravel particles are generally above those with gravel particles symmetrically located along the longitudinal axis, and (4) the G/Gmax – log γ relationships of all specimens were reasonably close for the nonlinear ranges covered in these tests (γ < 0.05 % and G/Gmax > 0.6). As long as the oversized particles were near the axis of rotation, the particles had little effect on the dynamic properties (Gmax, Dmin and G – log γ relationships) regardless of sizes and numbers of particles. However, once the oversized particles were located away from the axis of rotation and closer to the perimeter of…
author: Shin, Boonam
language: en
keywords: Dynamic properties, Oversized particles, Resonant column, Sand
date published: 2014-08
date modified: 2026-07-24T05:01:10Z
provider: University of Texas
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: The University of Texas at Austin

PropertyValue
property ID: Handle
value: http://hdl.handle.net/2152/27552