BYU Phase II - Dynamic Passive Pressure on Full-Scale Pile Caps

Brigham Young University (BYU) is one of the first universities selected to conduct research under the NEES program. BYU's research focuses on the behavior of soil behind a full-scale foundation when subjected to earthquake-like loadings. It is the backfill soil which helps prevent excessive horizontal movement of foundations during earthquakes. The amount of resistance provided by a backfill soil depends on many factors, including: soil type, soil density, and the potential amount of foundation movement. Horizontal forces from earthquakes introduce other factors such as large, repetitive movements and high rates of loading. The effects of these factors on soil resistance are not well quantified. This project will use loading rams (i.e., actuators) and a shaker mounted to a foundation to approximate an earthquake loading. The resistance provided by various backfill soils under different magnitudes and rates of cyclic loading will then be determined.

UCLA shaker and BYU actuators

Backfill with grid

Another backfill

UCLA shaker and BYU actuators without backfill

Noting the cracks in the backfill

Field trip to the site