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USGS · 70178058

Dynamic pore-pressure fluctuations in rapidly shearing granular materials

Richard M. Iverson·Richard G. Lahusen
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Abstract

Results from two types of experiments show that intergranular pore pressures fluctuated dynamically during rapid, steady shear deformation of water-saturated granular materials. During some fluctuations, the pore water locally supported all normal and shear stresses, while grain-contact stresses transiently fell to zero. Fluctuations also propagated outward from the shear zone; this process modifies grain-contact stresses in adjacent areas and potentially instigates shear-zone growth.

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Richard M. Iverson, Richard G. Lahusen. 1989. Dynamic pore-pressure fluctuations in rapidly shearing granular materials. https://doi.org/10.1126/science.246.4931.796

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