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Computational and experimental method for determining the specific heat capacity of dispersed soil and bound water

DOI: 10.17586/1606-4313-2019-18-4-92-97
UDC 556.113

Computational and experimental method for determining the specific heat capacity of dispersed soil and bound water

Timofeev A. M., Kravtsova O.N., Tappyrova N.I., Ivanov V.A., Protodyakonova N.A.

For citation: Timofeev A.M., Kravtsova O.N., Tappyrova N.I., Ivanov V.A., Protodyakonova N.A. Computational and experimental method for determining the specific heat capacity of dispersed soil and bound water. Vestnik Mezhdunarodnoi akademii kholoda. 2019. No 4. p.92-97

Abstract
When calculating the temperature regime of soils used as bases of buildings and engineering structures, it is necessary to take into account the specific heatcapacity. The specific heat capacity of soils is an additive value and is determined not only by the heat capacity of the soil skeleton, but also by the heat capacity of water. Bound water in dispersed soil significantly affects numerous properties of these soils as well as the processes of heat and mass transfer in them. This effect is most pronounced in dispersed soils such as clay. Therefore, the study of the properties of bound water remains relevant today. The article presents experimental data on the determination of sorption humidity, lower and upper limits of plasticity, and specific heat capacity of clay soil. Soil samples were taken from the Amginsky Deposit of the Republic of Sakha (Yakutia). Measurements of specific heatcapacity were carried out on samples of clay soil taken directly from the field and samples of the same soil, but pre-cleaned from impurities by the elutriation method. The values of the specific heat capacity of clay soil were obtained on the Sensys Evo TG-DSC differential scanning calorimeter. On the basis of these data, the calculation of specific heat capacity of the bound water in clay soil is made. Curves of changes in specific heat capacity of clay soil and bound water depending on humidity for two types of soil are given. It is concluded that for clay soil the dependence of specific heat capacity on humidity is not monotonous, as well as the specific heatcapacity of bound water.

Keywords: clay soil, specific heat, bound water, differential scanning calorimeter, sorption humidity, lower and upper limits of plasticity.

All references

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