Dynamic Back Pressured Shearbox

Large, rapid submarine landslides have the potential to generate tsunami with devastating effects on coastlines and offshore infrastructure. Their failure mechanisms are therefore important but remain to be fully understood. In particular, whilst the role of free gas and gas hydrates in progressive failure has been inferred from geophysical datasets, the physical mechanisms are not well-understood.

The Tuaheni Landslide Complex (TLC) is located on the upper slope of the Hikurangi Margin, off the East Coast of the North Island, New Zealand. They developed novel laboratory-based testing using gravity core samples from within the TLC and a Dynamic Back-Pressured Shearbox (DBPSB) from GDS Instruments to replicate offshore slope conditions. The DBPSB was used to test the behavior of the TLC in response to simplified earthquake shaking and increased pore-fluid (PWP) and pore-gas pressure (PGP) within the landslide mass.

Click here to download the case study.