Investigation of GPR Signals Parameters Changes during Defrosting Process of Frozen Dispersed Rocks of Different Humidity

Fedorova L.L., Savvin D.V., Sokolov K.O., Kulyandin G.A.


Laboratory studies are conducted on dispersed rock samples of different moisture content frozen in a refrigerating chamber, with the subsequent defrosting at temperature 22°С. According to the results of sensing by GPR OKO-2 with a center frequency of 1200 MHz delay time, amplitudes and spectral characteristic of the signals at varying moisture (from 3 to 20%) and temperature (from -15 to 15 °C) of rocks were determined. The results of the research showed a significant difference between the velocity of GPR signals at negative and positive temperatures for two types of sands of Quaternary deposits with a moisture content more than 7%. GPR amplitude values of signals and their frequency composition are described, depending on the temperature and humidity of the samples. The obtained results will serve as a basis for creation of automated system for determining the variation of the moisture in the rocks and display the data through geographic information system, which will greatly facilitate the control of moisture content of rocks in the mining industry. Application of the developed system is promising for monitoring of rock properties of pit walls and roofs of mine openings and soil foundations of engineering structures.

Key words: ground penetrating radar, dispersed rocks, defrost, humidity, temperature, dielectric permittivity, mining facilities, permafrost.

Science and Education, 2016, No.3, pp.42-46