基于数字化CSIRO双温补偿方法的岩体扰动应力长期监测系统的研发与应用

The stress disturbance of surrounding rock is the direct factor causing the instability and failure of engineering.However, at present, there are no effective methods and techniques to obtain the stress disturbance of surrounding rocks. With the development of deep rock mechanics and mining theory, disturbance stress monitoring has become an important subject. Using the basic theory of CSIRO, this study put forward the twin temperature compensation, developed the stress monitoring techniques, and realized the real-time monitoring of rock mass disturbance stress in the engineering. Considering the great temperature effect of the environment, the unstable power supply and the small collection channel adjustment in the long-term monitoring, the collection system with function of data-connection is developed when the power is cut off and reconnected. Based on the technique of CSIRO cell basic theory and the complete temperature compensation method, the twin temperature compensation method was proposed to collect and measure circuits, and to calibrate the acquisition circuit. Considering the characteristics of stress monitoring environment, the strain gauge cloth plan of the rock mass close to excavating surface was designed, and based on the in-situ stress measurement principle, the measure strain and stress relationship formula was deduced. The improved circuit adjustment is used for measuring the wide range of the measurement channel, and the high precision thermistor is applied to monitor the measured temperature. Using the function of data-connection when the power is cut off, the monitoring data of the discontinuous conventional collecting circuit is overcome, and the measured 20 days of power failure in laboratory tests meet the requirement of measuring accuracy. According to the calibrated data in laboratory, the influence of temperature on the precision of monitoring system is effectively eliminated by the twin temperature compensation method. Aiming at the rock slope and underground chamber, different rock mass disturbance stress long-term monitoring systems are designed and developed. Field application test displays that, the rock mass disturbance stress long-term monitoring system fully reflects the advantages of power cut and twin temperature compensation. The results calculated by the relationship between strain and stress shows that the system can effectively monitor the rock mass disturbance stress.