SOIL STRENGTH PARAMETERS DETERMINED BY COMPRESSION TEST

G.P. Postoev, A.I. Kazeev, V.N. Kutergin

Sergeev Institute of Environmental Geosciences, Russian Academy of Sciences, Ulansky per. 13, str.2, Moscow, 101000 Russia.

E-mail: opolzen@geoenv.ru, www.opolzni.ru.

The determination of actual soil strength in a soil massif in its natural bedding conditions is among the main problems of soil mechanics, engineering geology and geoecology. These parameters are used in the stability analysis, for the assessment of soil massif deformations upon its interaction with engineering structures, as well as in the study of hazardous geological processes. A direct shear test is the most com- mon method of determining soil strength characteristics. The disadvantage of this method is the necessity of testing of no less than 3 samples per each engineering-geological element. A new method for de- termination of consolidated soil strength characteristics by a compression test of a soil sample has been developed at IEG RAS. The lateral stress measured in the course of one test allows obtaining the values of cohesion, angle of internal friction and structural strength. The method does not require building the envelope line of limit Mohr`s circles. Thus, the proposed method for the determination of soil strength characteristics can significantly reduce the cost of laboratory tests and labor costs. It increases the ac- curacy of determination of soil strength characteristics. Inevitable methodological errors are excluded, which are related to the preservation of natural soil structure (in a sample) and condition, and ensure the homogeneity of samples upon engineering geological survey.

Keywords: soil strength properties, soil structural strength, Coulomb-Mohr criterion, angle of internal friction, cohesion, lateral stress, compression testing.

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