Investigation of Geophysical Methods for Assessing Seepage and Internal Erosion in Embankment Dams: Laboratory Testing of the Streaming Potential Phenomenon in Soils

This report presents the results of a laboratory investigation of the streaming potential phenomenon in soils to develop the level of understanding and to improve the methods currently used to interpret self-potential survey data relating to the study of seepage conditions in embankment dams. The report describes the design and development of a laboratory apparatus and procedures specific to measurements of the streaming potential phenomenon and resistivity in reconstituted soil samples. The apparatus enables measurement of the streaming current cross-coupling coefficient using both unidirectional and cyclic flow methods, as well as the measurement of sample resistivity using the DC resistivity method. The influence of soil and fluid properties on the streaming current cross-coupling coefficient and resistivity of saturated soil samples is studied using samples of glass beads and representative embankment materials. Values of the streaming current cross-coupling conductivity and resistivity are characterized for samples of representative sand and gravel shell and glacial till core material from an embankment dam site in British Columbia. This volume marks one of a series of reports on the subject of geophysical methods and their use in assessing seepage and internal erosion in embankment dams.