Comparative Study on the Prevention and Control Effects of Rockburst Between Hydraulic Fracturing Sections and Blank Sections.

Influenced by various factors such as the complex environment and high key layers in coal mines, hydraulic fracturing technology has gradually become the main means of controlling the hard roof strata to prevent and control rockburst in recent years, which can effectively release the stress on the roof, reduce the intensity of pressure, and ensure the safe and efficient mining of the working face in coal mines. However, the current research on hydraulic fracturing to prevent and control rockburst is mostly limited to optimizing fracturing parameters and monitoring and evaluating fracturing effects, and there are few studies on blank sections, which cannot guarantee the overall prevention and control effect of rockburst, or increase unnecessary construction costs. In this paper, for the directional long borehole staged hydraulic fracturing project, triangular-type blank sections and regular-type blank sections are defined, and the rockburst prevention and control effects of fracturing sections and triangular-type blank sections during fracturing are compared and analyzed by the underground-ground integrated microseismic monitoring technology and transient electromagnetic detection technology, and the rockburst prevention and control effects of fracturing sections and regular-type blank sections during the coal extraction period are compared and analyzed by the underground-ground integrated microseismic monitoring data such as microseismic energy level and frequency as well as the online stress monitoring data.

A Combined Method of Seismic Monitoring and Transient Electromagnetic Detection for the Evaluation of Hydraulic Fracturing Effect in Coal Burst Prevention.

In order to mitigate the risk of roof-dominated coal burst in underground coal mining, horizontal long borehole staged hydraulic fracturing technology has been prevailingly employed to facilitate the weakening treatment of the hard roof in advance. Such weakening effect, however, can hardly be evaluated, which leads to a lack of a basis in which to design the schemes and parameters of hydraulic fracturing. In this study, a combined underground-ground integrated microseismic monitoring and transient electromagnetic detection method was utilized to carry out simultaneous evaluations of the seismic responses to each staged fracturing and the apparent resistivity changes before and after all finished fracturing.