Incorporating inherent uncertainties in seismic liquefaction assessments


Liquefaction assessments for tailings facilities have significant uncertainty, yet their results are typically presented as single-value deterministic factors of safety (FoSs) to compare against standard practice guidance. Some of the uncertainty is due to inherent material variability or measurement error associated with in situ testing techniques. 
There is also a considerable – and often ignored – contribution from the transformation models used to convert in situ measurements to design parameters. For seismic liquefaction assessments, the key sources of transformation model uncertainty are from the empirical relationships relating standard penetration testing or cone penetration testing (CPT) results to cyclic resistance and residual undrained strength. While the uncertainties associated with the material variability and measurement error will vary by site and can usually be reduced through additional investigation, the model uncertainties are constant and irreducible without further work. 
This lecture will discuss how the transformation model uncertainties associated with CPT-based liquefaction assessments can be incorporated into design practice to estimate probabilities of failure and lead to very different outcomes than simply considering FoS alone

About the Speaker

Holly Williams has an undergraduate degree in civil engineering and a master’s degree in data science.  She specializes in the application of data science and statistical approaches to incorporate risks and uncertainties into mine waste studies and designs.  Her experience includes tailings facility designs (from site-selection and alternatives assessments through to detailed design and construction oversight), dam break assessments, water balance studies, mine reclamation and closure designs, and risk assessments for wide range of projects in in Canada, USA, Mexico, Australia, South America, Europe, Russia, and Africa.

Further information

This event is organised by SECED. The event will be chaired by Guillermo Aldama-Bustos (Jacobs) . Attendance at this meeting is free for members and non-members alike. 

Online attendance

This event will be broadcast online. Please register for the event prior to joining. The registration process will provide you with the link you need to join the main event.

Link here

*Recording of the evening meeting is available here:

Incorporating inherent uncertainties in seismic liquefaction assessments | Institution of Civil Engineers (ICE)

Event Details

Event Date 31/01/2024 6:00 pm
Event End Date 31/01/2024 8:00 pm