[Objective] With coal mining depth continuously advancing to the kilometer level, the dynamic evolution characteristics of mining-induced stress fields have become a crucial challenge for deep surrounding rock stability control and dynamic disaster early warning. Existing traditional monitoring equipment is limited by uniaxial measurement, and suffers from insufficient monitoring sensitivity and poor long-term stability in heterogeneous media such as coal and rock masses, failing to meet the precise monitoring needs of deep mining.[Methods] This study proposes a new type of volumetric mining-induced stress monitoring sensor. Through complete coupling between its cylindrical sensing structure and the surrounding rock of the borehole, it breaks through the uniaxial measurement limitation of traditional equipment, enabling real-time monitoring of mining-induced stress changes caused by micro-deformations of surrounding rock masses. [Results] Laboratory tests, field tests, and application results show the following:①In laboratory tests, the pressure change output by the sensor shows a highly linear relationship with axial stress, with a sensitivity of 0.456, which is better than that of traditional stress gauges;②Long-term stability tests indicate that under high and low stress environments, the sensor’s pressure fluctuations show no continuous drift or data jumps, demonstrating good long-term monitoring stability;③Temperature characteristic experiments reveal a linear relationship between temperature and pressure changes, verifying the universality of the temperature compensation formula;④In the field application at Yadian Coal Mine in Binchang Mining Area, Shaanxi Province, the sensor successfully captured stress fluctuations synchronized with the mining cycle. In sudden stress events such as roof fractures, its response speed and accuracy were significantly better than traditional equipment, and the monitoring data showed a strong correlation with microseismic monitoring results;⑤In the test in hard rock environments of metal mines, the sensor also exhibited long-term stable monitoring capability. [Conclusion] ①The new volumetric mining-induced stress monitoring sensor breaks through the uniaxial measurement limitation of traditional equipment, significantly improving monitoring sensitivity and long-term stability in heterogeneous media;②Laboratory tests verify its linear response characteristics, high sensitivity, and temperature adaptability, while field applications prove that it can effectively capture the dynamic evolution characteristics of mining-induced stress;③The sensor can work stably in different mining environments such as coal mines and metal mines, showing strong applicability. [Significance] This research solves the key problems of insufficient monitoring sensitivity and poor long-term stability of mining-induced stress in deep heterogeneous media. It provides reliable technical support for capturing precursor information of dynamic disasters in deep mines and early warning of delayed rockbursts in tunnels, with important scientific value and application innovation.
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