Сравнение температурных замеров грунтов с помощью статического зондирования и скважинной термометрии

Development of infrastructure located in cryolithozone requires the use of modern geotechnical technologies for frozen soil investigation. Accurate soil temperature measurement is the necessary condition for engineering-geocryological survey and geotechnical monitoring. In the article a new method is considered on how to measure soil temperature by cone penetration testing (CPT). The cone temperature stabilization is described in detail, including the existing criteria of thermal stabilization of a cone. The results of temperature measurements are presented for both frozen and non-frozen soils and obtained by CPT (cone with a temperature sensor) and using borehole thermometry (thermistor string), which measured in both holes drilled by a rig and left after the cone penetration testing completion. Detailed analysis of accuracy of soil temperature measurement is also provided. The comparison of the obtained results is performed and the discrepancy of the measured soil temperature in absolute values is estimated. As a result of the analysis, it was shown that all the soil temperature values measured by different methods are sufficiently close to each other and the true value of the natural soil temperature are all located in the zone of intersection of the confidence intervals of each temperature measurement, performed at corresponding depths by different methods. All obtained temperature values do not cross the accuracy limits of temperature sensors, used both in cone penetration testing and borehole thermometry. High accuracy of temperature measurement by CPT is proved and feasibility of CPT application for soil temperature measurement is justified as an express-monitoring method.