The pattern of changes in the velocity of propagation of ultrasonic waves in frozen soil samples during thawing

Abstract

The locations of mining and processing enterprises in the areas of permafrost distribution are associated with monitoring the state of the ice-ground massif. The monitoring problem is exacerbated by climate change trends, and the reduction of suitable for the existence of permafrost zones. The increase in the number of emergencies associated with the degradation of permafrost soils in the regions of the Republic of Sakha and the Norilsk industrial region are direct evidence of this problem. The main consequences of thawing soils are uneven troughs of subsidence of foundations, frosty swelling, and waterlogging. The article considers the possibility of using the ultrasonic monitoring method in order to monitor the state of permafrost soils, along with existing monitoring methods. Existing methods for monitoring the state of permafrost soils are considered. The results of experimental studies of changes in the velocity of propagation of an ultrasonic wave during the thawing of various permafrost soils, humidity and particle size distribution are presented. It has been proved experimentally that the sensitivity of the speed of propagation of an ultrasonic wave to a change in temperature in frozen soil samples. When the soil passes from a frozen state to a plastic-frozen state, there occurs a sharp drop in the speed of the ultrasonic propagation.