Recently, Limin Company of Wuhai Energy received an invention patent certificate issued by the China National Intellectual Property Administration for its Early Warning Method, Device and Coal Mine Early Warning System for Coal Mine Rock Bursts. The company made new progress in its research in coal mine rock burst prevention.
The system established a multi-dimensional early warning index system including stress value, stress increase rate and stress increase range. It put forward a dynamic early warning method for coal mine rock bursts based on multi-source stress index fusion. This method addressed the pain points of poor adaptability, low accuracy and weak reliability caused by traditional early warning with a single stress increment index, and realized precise assessment of rock burst risk. Stress value indicators were divided into shallow hole and deep hole categories. Stress growth rate indicators adopted a 2-hour short-term growth rate and 24-hour long-term growth rate to capture short-term sudden changes and long-term trends of stress, reflecting stress accumulation.
The system set judgment standards for different risk levels based on uniaxial compressive strength of coal seam. It determined the influence coefficient of goaf with the cuttings method, built an absolute stress estimation model and defined multi-level early warning intervals. Through data preprocessing, index calculation and weight distribution, it conducted comprehensive evaluation via a weighted linear combination model and classified risks into none, weak, medium and strong levels. The system broke through the limitations of single indexes, enriched index information, solved the adaptability issue of fixed weights and strengthened the correlation between early warning results and actual risks, providing a scientific basis and technical support for safe production in coal mines.
