Mechanisms and Implications of Time-Dependent Changes in the State and Properties of Recently Liquefied Sands (NEES-2006-0166)

<p><strong>Title</strong>: Mechanisms and Implications of Time-Dependent Changes in the State and Properties of Recently Liquefied Sands (NEES-2006-0166)</p> <p><b>Year Of Curation: </b>2011</p> <p><b>Description: </b>The overall objective of the proposed research is to improve the understanding of the sand aging mechanisms and to better quantify aging influences on engineering properties. Towards this end, the proposed research is subdivided into the following five Tasks, involving synergistic field and laboratory investigations:</p> <ol> <li>Site characterization</li> <li>Field aging study: induction of liquefaction by explosives, vibrocompaction and vibroseis and the monitoring of post-liquefaction time-dependent changes in state and engineering properties in the post-liquefied sand</li> <li>Laboratory study to quantify scale effects</li> <li>Parametric study in the laboratory to discern and quantify the influence of each variable on aging. 5. Development of an analytical model for a QA metric for remedially densified sand that accounts for aging effects</li> </ol> <p>Experiment 1 (Univ. of Michigan, Univ. of Texas at Austin): We made several trips to a quarry owned by Mulzer Crushed Stone, Inc. in Griffin, IN. In July 2007, we performed two VisCPTs. In October 2008, we performed two SCPTs and three CPTs.</p> <p>Experiment 2 (Univ. of Texas at Austin): Vibroseis shaking was used to disturb a loose sand layer that began roughly 1.5 meters below the ground surface. In-situ tests were conducted to record the soil strength and stiffness changes with time following the disturbance.</p> <p>Experiment 3 (Univ. of Texas at Austin): In-situ testing was performed in the shake areas to determine if the test results changed with time following disturbance by vibroseis shaking. Testing included DMT, CPT, VisCPT, SCPT, down-hole, and cross-hole testing.</p> <p><b>Award: </b>https://www.nsf.gov/awardsearch/showAward?AWD_ID=0530378</p> <p><b>PIs & CoPIs: </b>Russell Green, Roman Hryciw, Christopher Baxter</p> <p><b>Dates: </b>September 15, 2005 - August 31, 2010</p> <p><b>Organizations: </b>University of Michigan, University of Texas at Austin</p> <p><b>Facilities: </b>University of Michigan, Ann Arbor, MI, United States,    University of Texas at Austin, TX, United States</p> <p><b>Sponsor: </b>NSF - 0530378</p> <p><b>Keywords: </b>Cone Penetration Test, Dilatometer Test, shear wave velocity, Liquefied Sand, Sand Aging, Vibroseis</p> <p><b>Publications:</b></p> <p>Saftner, David A. (2011). “Time-Dependent Strength Gain in Recently Disturbed Granular Materials. Thesis. University of Michigan.</p> <p>Saftner, D. A.; Hryciw, R. D.; Green, R. A.; Lynch, J. P.; Michalowski, R. L.  (2008). The Use of Wireless Sensors in Geotechnical Field Applications</p> <p>Jirathanathaworn, T.; Hryciw, R. D.; Green, R. A. (2010). Photoelastic Sensors for Measurement of K o</p> <p>Saftner, D.; Green, R.; Hryciw, R.; Lynch, J. (2008). Instrumentation for the NEESR Sand Aging Field Experiment</p> <p>Leclerc, Meghan C. (2008). Evaluation of Gas Dissipation as a Mechanism for Aging of Sands</p> <p>Green, R. A., Hryciw, R. D., Saftner, D. A., Baxter, C. D. P., Jung, Y., &</p> <p>Jirathanathaworn, T.  (2008). Sand Aging Field Study</p> <p>Jung, Yongsub (2010). Determination of soil grain size distribution by soil sedimentation and image processing</p> <p>Jirathanathaworn, Thaweesak (2009). Development of photoelastic methods towards study of mechanical aging of 2-dimensional granular assemblies</p> <p>Lee, Jongwon (2009). Engineering characterization of earthquake ground motions</p> <p>Polito, Carmine P.; Green, Russell A.; Lee, Jongwon (2008). Pore pressure generation models for sands and silty soils subjected to cyclic loading</p> <nb:citations></nb:citations>