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Determination of Compression Index for Sandy Soil
by Triaxial Compression Test
Koji MISUMI*, Syohei NOMURA** and Tatsuro HIKIDA
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The determination procedure of sandy soil’s compression index is proposed newly in this paper. At first, a series of triaxial compression test datum are obtained under constant mean normal stress condition. Secondly, this method is carried out by fitting some equations to sandy soil’s shearing behaviors (i.e., dilatancy behaviors). Finally, sandy soil’s compression index is obtained by relationship between maximum positive volumetric strains and initial specific volumes. The validity of this method is confirmed by applying to local soil Shirasu.
Keywords : compression index, triaxial compression test, dilatancy, Shirasu
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11) J. H. Atkinson and P. L. Bransby, The Mechanics of Soils, An Introduction to Critical State Soil Mechanics, McGRAW-Hill Book Company Limited, pp.235-262 (1978).
A. Schofield and P. Wroth, Critical State Soil Mechanics, McGRAW-Hill Publishing Company Limited, pp.124-127 (1968).
