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:

1. Site characterization
2. 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
3. Laboratory study to quantify scale effects
4. 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

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.

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.

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.