Determination of Strength Characteristics of Rocks in Air-Dry and Water-Saturated State

The strength characteristics of the rock in the air-dry and water-saturated state must be taken into account when performing geotechnical calculations for the first limit state when designing various hydraulic structures, as well as for any other structures that interact with water and have an increased class of responsibility. In this regard, experimental studies were carried out on samples of gneiss, limestone and pebbles in order to determine their strength characteristics in two different states: in air-dry and water-saturated. Based on the results of the experimental studies carried out, rock strength passports were constructed based on the determination of the strength limits under uniaxial compression and tension in air-dry and water-saturated states, and the strength characteristics and the softening coefficient of the rock were determined. It is found that water saturation of rock samples leads to a decrease in their strength characteristics, and the softening coefficient of gneiss decreases with increasing depth of occurrence. Taking into account the influence of various factors and conditions on the obtained test results, further laboratory studies are necessary in order to develop methods for assessing changes in strength characteristics at different water saturation of the rock and the depth of its occurrence.

L.Yu. ERMOSHINA, Master, Postgraduate Student, Junior Researcher at the SEC “Geotechnics” named after Z.G. Ter-Martirosyan (This email address is being protected from spambots. You need JavaScript enabled to view it.),
A.E. SHIPKOVA, Student (This email address is being protected from spambots. You need JavaScript enabled to view it.),
A.Z. TER-MARTIROSYAN, Professor, Doctor of Sciences (Engineering) (This email address is being protected from spambots. You need JavaScript enabled to view it.),
G.O. ANZHELO, Candidate of Sciences (Engineering)(This email address is being protected from spambots. You need JavaScript enabled to view it.)

National Research Moscow State University of Civil Engineering (26, Yaroslavskoe Highway, Moscow, 129337, Russian Federation)

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