Title page for ETD etd-09212012-220649


Type of Document Dissertation
Author Suarez Zambrano, Nestor Ricardo
Author's Email Address nsuarez@vt.edu
URN etd-09212012-220649
Title Micromechanical Aspects of Aging in Granular Soils
Degree PhD
Department Civil Engineering
Advisory Committee
Advisor Name Title
Brandon, Thomas L. Committee Chair
Mitchell, James K. Committee Co-Chair
Filz, George M. Committee Member
Green, Russell A. Committee Member
Keywords
  • aging
  • creep
  • sand
  • acoustic emissions
  • computed tomography
  • discrete element method
  • rate process theory
Date of Defense 2012-09-03
Availability unrestricted
Abstract
Granular soils exhibit a generally beneficial change in engineering properties with time after deposition or densification, during a process commonly known as aging. Soil properties reported to change during aging include the small strain modulus and stiffness, penetration resistance, liquefaction resistance, and pile setup. Different hypotheses have been proposed to explain the occurrence of aging in granular soils, including cementation induced by dissolution of silica and precipitation at the particle contacts, cementation due to microbiological activity, internal stress redistribution caused by particle crushing, and buckling of the load chains due to particle slippage. New evidence points out that internal and time-dependent changes in the soil structure caused by particle slippage and rearrangement as the source of the time-dependent variations in soil properties.

This investigation is focused on the study of aging at the particle scale to determine its main driving mechanism and define the factors which affect it. Results from an extensive laboratory testing program and computer simulations based on the discrete element method provide insight into the causes of aging and its effects on the macroscopic properties of sands based on the analysis of the interaction between sand grains.

Files
  Filename       Size       Approximate Download Time (Hours:Minutes:Seconds) 
 
 28.8 Modem   56K Modem   ISDN (64 Kb)   ISDN (128 Kb)   Higher-speed Access 
  Suarez_NR_D_2012_2.pdf 28.19 Mb 02:10:29 01:07:06 00:58:43 00:29:21 00:02:30

Browse All Available ETDs by ( Author | Department )

dla home
etds imagebase journals news ereserve special collections
virgnia tech home contact dla university libraries

If you have questions or technical problems, please Contact DLA.