Explosive Induced Pore Pressure in a Sandfill Dam

This paper reports on the potential performance of earthfill and tailings dams, and other saturated earthen structures, subjected to blast vibrations. Relationships between explosive-induced residual pore pressure increase and crest settlement versus peak particle velocity are presented. Eight explosive tests, conducted on a 2.25-m-high dam constructed of loose dilative sand, showed that significant increases in residual pore pressure (PPR > 0.1) occurred when peak particle velocity exceeded 0.015 m/s at shallow depths to 0.035 m/s at greater depths. Limited crest settlement occurred when the peak particle velocity exceeded 0.025 m/s. Results of this research, previous research, and the field behavior of full-scale earthfill and tailings dams indicate that peak particle velocity below 0.025 m/s and 0.10 m/s are reasonable thresholds to limit pore pressure buildup in full-size earthfill and tailings dams sensitive and not sensitive to vibrations, respectively.