Method for Determination of Thermal Conductivity of Sand, Silt and Silty Clay

Abstract

The invention provides a method for determining the thermal conductivity of sand, silt and silty clay. The method comprises the steps of: obtaining the temperature interval at which phase transition of water in the soil begins to occur and the temperature at which water completely freezes according to the freezing temperature test of the soil. interval; according to the thermal conductivity of sandy soil, silt and silty clay at different dry densities, saturations and temperatures, the relationship between thermal conductivity and dry density, saturation and temperature in the unfrozen state, frozen state and completely frozen state was respectively established Three-parameter data model; regression equation derived from least squares analysis of data, leading to empirical formulas for thermal conductivity with respect to dry density, saturation and temperature. The effect of the present invention is that the thermal conductivity of sand, silt and silty clay at any dry density, saturation and freezing temperature can be quickly determined, and accurate thermal conductivity values ​​can be provided for the calculation of the temperature field, so that the temperature field can be simulated and calculated closer to reality. Important parameters such as the thickness of the frozen wall, the average temperature of the frozen wall, and the strength of the frozen wall can be predicted.

Description

technical field [0001] The invention relates to a method for determining thermal conductivity, in particular to a method for determining thermal conductivity of sandy soil, silt and silty clay. Background technique [0002] With the development of society and economy, the design and research of many engineering technical problems need to determine the thermophysical parameters of soil in advance. Such as heat conduction calculation and analysis of underground buildings and facilities, underground heat storage (cold) technology, etc. Soil thermal conductivity test and theoretical research is an important aspect of research on frozen soil engineering, soil temperature field moisture migration, and foundation temperature field changes, which affect the design and construction of the above problems. With the widespread application of freezing method construction technology, the thermophysical parameters of soil materials have gradually become the focus of research. [0003] Th...

AI Technical Summary

Problems solved by technology

However, the process of obtaining the accurate thermal conductivity of the soil is very cumbersome. The relevant domestic regulations only list four typical soils in the form of peat silty clay, silty-silty clay, crushed stone silty clay and gravel in different dry conditions. Thermal conductivity at density and moisture content, but does not address saturation and temperature effects on thermal conductivity

The typical thermal conductivity can be determined by interpolation or epitaxy of the specification data, but there is no reliable basis for the thermal conductivity of other types of soil

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