Experimental Studies of the Thermo-Physical Properties of Soil Fixed by the Method of Jet Grouting

The transformation of weak soil foundations during the construction of buildings and structures in the permafrost zone can be considered as a constructive measure that makes it possible to ensure their long-term operational suitability in climate warming. Innovative for permafrost is the stabilization of soil using jet grouting technology, as a result of which a new material is formed – soil cement. At the moment, the thermal-physical properties of the soil cement necessary for predicting the thermal stress-strain state of the transformed bases from permafrost soils under climate warming conditions have not been studied. The normative documents do not contain the thermo-physical characteristics of soil cement, taking into account the soils in its composition and the technology of the arrangement of soil cement elements. As a result of laboratory tests conducted at the NIISF RAACS, the density, humidity, water absorption, and thermal conductivity of the cement soil samples were determined. The coefficient of thermal conductivity λ was measured by the IVTP-12 device, the principle of operation of which is based on the dielcometric method of measuring the properties of materials. For the first time, the characteristics of the thermal conductivity of soil cement in the thawed (λ_th) and frozen (λ_f) state were determined at different water content values W and density ρ of the samples. For the soil cement obtained in clay and sandy soils, graphs were constructed and dependences of thermal conductivity of soil cement on its density were established.

N.S. NIKIFOROVA¹, Doctor of Sciences (Engineering) (This email address is being protected from spambots. You need JavaScript enabled to view it.);
O.A. MAKOVETSKY², Doctor of Sciences (Engineering);
I.V. BESSONOV³, Candidate of Sciences (Engineering),
A.V. KONNOV³, Candidate of Sciences (Engineering)

¹ National Research Moscow State University of Civil Engineering (26, Yaroslavskoye Shosse, Moscow, 129337, Russian Federation)
³ Perm National Research Polytechnic University (29, Komsomolsky Prospect, Perm, 614000, Russian Federation)
³ Scientific-Research Institute of Building Physics of RAACS (21, Lokomotivniy Driveway, Moscow, 127238, Russian Federation)

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