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The monitoring system of rock mass stability and activity characteristic was established using the microseismic monitoring technology in view of the problem that the dynamic disaster of ground pressure was easy to occur in the process of deep mining. The monitoring network was set up according to the actual characteristics of the mine and the wave velocity was corrected by the method of fixed-point blasting. A monitoring network with a positioning error of 10 m was established finally. The waveform of the monitoring data was picked up and the temporal-spatial evolution characteristics of microseismic events were analyzed, the microseismic events increased greatly and in a high level, the spatial distribution was concentrated highly, the potential dangerous areas were delineated. The research results can provide references for the investigation of rock mass stability monitoring in underground engineering.

In order to solve the problem that shallow water source wells in northern pastoral areas are prone to freezing in winter, which brings inconvenience to drinking water for local residents. shallow water source wells are taken as the research object. Through field experiments indoor and software simulations, the key factors to prevent freezing of water source wells are discovered by obtained temperature distribution pattern of water source wells,A photovoltaic heating system compatible with existing solar water extraction systems in pastoral areas is designed. It is found that the temperature distribution of water source wells is “steep-slow- slow” in the field and extreme conditions. The steep-rising areas are located at 0.0-1.3m, 0.0-0.8m away from the wellhead, and the temperature rising rates in the steep-rising areas are 10.58 C/m and 15.75 C/m, respectively. Increasing the temperature of “steep rise zone” is very important to improve the water surface temperature of water source wells. The ANSYS software was used to simulate the temperature field of the water source well under extreme conditions (-40℃), and compared with the indoor simulation results to verify its accuracy. A photovoltaic heating system compatible with the existing solar water lifting system in the pastoral area was designed which can generate 1659.52J heat a day larger than 412.2J heat dissipation per day under extreme conditions which is calculated by software model. Theoretically this system can meet antifreeze requirements. An indoor anti-freezing experiment of solar heating for a freezing period (3 months) was carried out. It was found that the temperature at the water surface of the water source well was about 0℃, which verified the feasibility of the solar heating system.