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This paper gives the results of experimental research of temperature variation and its effect on distribution of moisture in pavement and subgrade of a highway located in the eastern region of Kazakhstan. The sensors consisting of two elements have been used to measure temperature and moisture. The first of them is designed for measurement of temperature and based on the effect of thermal resistance, and the second one based on diamagnetic penetration allows measuring of moisture. Peculiarities of temperature variation in time in pavement layers and points of subgrade, temperature distribution in the depth at different time moments have been described. Important characteristics have been determined – duration of a frozen condition and freezing, average rates of freezing and defreezing in points of pavement and subgrade located in various depths. Quantity of unfrozen water in subgrade soil depends on negative temperature and initial moisture and it is satisfactorily approximated by semi-logarithmic function. Keywords: Pavement, Subgrade, Sensors, Temperature, Moisture, Unfrozen water

The paper investigates experimentally the distribution, variation in time of a temperature and moisture in a pavement and subgrade of a highway located in the south of Kazakhstan. Sensors designed in the form of a metal capsule containing the element for temperature measurement through thermal resistance and the element for moisture measurement on diamagnetic permeability have been used for measuring. Peculiarities have been described for daily, quasi-seasonal and annual cyclic variation of temperature and moisture in the pavement and subgrade. Quantitative characteristics have been determined and statistically evaluated for cyclic freezing and thawing (number of freezing and thawing cycles, a minimal temperature in cycles, frozen condition duration) in the pavement points. Data have been shown for freezing and thawing processes of the pavement. Unfrozen water content has been quantitatively described in the base layer of the pavement depending on a negative temperature.