Dynamic Measurements and Porosity in Saturated Triaxial Specimens
Recent work has shown how soil porosity may be obtained from elastic wave measurements in the field. The procedure is based on Biot poroelastic theory, and employs both S-wave and P-wave measurements. Only a limited amount of laboratory tests has been employed to date to substantiate this procedure. All of them relate to sand samples, in tests where porosity variation was small. In this work we apply the poroelastic procedure to infer porosity during triaxial tests instrumented with piezoelectric transducers. The materials tested, Bothkennar clay and Porto granite residual soil, have large variations in porosity, variations that are independently measured. The results would offer some light on the applicability of the poroelastic procedure to the frequency testing range common in laboratory applications.
KeywordsLaboratory Stiffness Dynamics Elasticity Numerical Modelling
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