CIES Seminar - understanding of internal erosion in zoned embankment dams

Abstract:

Embankment dams fail as a consequence of overtopping, rotational slips, else internal erosion. A combination of material susceptibility, effective stress, and hydraulic loading govern the probability of internal erosion. The state-of-practice is currently limited to an empirical assessment of material susceptibility.

Following a review of select dam safety incidents, and the state-of-practice, the novel features of a triaxial-permeameter (TXP) and a flexible wall permeameter (FXP) are reported, both of which have been designed and commissioned to advance a mechanics-based understanding of erosion by internal instability. Test specimens are reconstituted by moist-tamping, using soil obtained from the Bennett South Moraine (BSM) borrow source of the WAC Bennett Dam in British Columbia, Canada.

Results from the FXP device are being used to characterize material susceptibility in stress-gradient space. Results from the TXP device are being used to establish the consequences of erosion within a critical state soil mechanics framework. Progress is reported on the multi-year program of research, undertaken with industry funding from BC Hydro.

Bio:

Professor Jonathan Fannin studied civil engineering at the Queens University of Belfast and, upon completion of his doctoral studies at Oxford University, worked at the Norwegian Geotechnical Institute before taking an appointment at the University of British Columbia. His longstanding research interests address internal erosion of zoned embankment dams, debris flow risk, and geosynthetics for ground improvement.

CIES Contact:

Dr Kurt Douglas ([email protected])

Professor Adrian Russel ([email protected])

Host or Publisher School of Civil and Environmental Engineering