土または岩石における超音波伝播速度とその力学特性

Abstract

This is a report on the followings: (1) the comparison of the dynamic elastic constants of soils and rocks determined by ultrasonic methode with static one, (2) the in-vestigation of the possibility of estimating the compressive strength from the dynamicshear modulus, (3) the influence of pore fluids on ultrasonic velocities in soils.From the measurements of ultrasonic velocities in soils and rocks, and the uniaxialcompression tests, the following results are obtained. (1) In relatively isotropic materialssuch as soils and mortars, the dynamic shear modulus Ga increases with the compressiveStrength qu and qu/Ga increases with qu (Fig. 4 and Fig. 5). (2) The longitudinal wavevelocity Vi in soils is influenced by pore fluids and the present of air in pore causes thedecrease in Vi (Fig. 9). (3) The dynamic Young's modulus Ea increases with the increaseof the static one Es (Fig. 10) and it seems that the relationship between Ea and Ea/Esis approximately represented by hyperbola (Fig. 11 and Fig.12).