Centrifuge test SSK01 on prefabricated vertical drains for liquefaction remediation

This is the first test in a series of three dynamic centrifuge tests designed to evaluate the effectiveness of prefabricated vertical drains in mitigating liquefaction. Centrifuge testing was performed using the 9-m radius centrifuge at the NEES@UCDavis Center for Geotechnical Modeling. The centrifuge model consisted of sloping ground with liquefiable sand overlain by a low-permeability crust. Water was used as the pore fluid. A centrifugal acceleration of 15g was applied.

The centrifuge model featured untreated and drain-treated mildly sloping (3 degree) soil profiles separated by a central channel. Each slope was
comprised of a 4 to 5 m thick (prototype scale) layer of liquefiable sand overlain by a 1 m thick (prototype scale) clay cap. Accelerometers and pore pressure transducers and linear potentiometers were placed within the model to measure its response.

The model was subjected to 12 sinusoidal accelearation-time history input motions, each with 20 cycles of motion at a frequency of 2 Hz (prototype scale), and shaking was performed parallel to the slope. The amplitudes of the first three shaking events were too small to be captured by the sensors. The remaining shaking events ranged in PGA from 0.01 g to 0.3 g.

***Final data report - now available in the "documentation" tab!!***