Simulation Experiment Monitoring System For Influence Of Key Strata Movement On Roof Weighting And Its Application

The deformation, failure and movement of overlying key stratum fundamentally induce the strata behaviors in face. In-situ measurement and simulating experiment are is the main approach to study the internal link between overlying key strata movement and strata behaviors. For the shortage of In-situ measurement, such as long period, high cost, limited scope, inner invisibility, physical simulating experiment become a effective complementary method. But, there was no available method for synchronous dynamic quantitative observation on overlying strata movement index(amount of strata movement, stress transformation between strata) and strata behavior index(resistance of hydraulic supports) in physical simulating experiments. Therefore, this thesis focused on the overlying strata – stope joint observation method for plane physical simulating experiments.Based on key stratum theory in ground control and aforementioned strata behavior –overlying strata integrated research mode, key strata – stope joint observation method for physical simulating experiments was proposed, meanwhile, the corresponding key strata – stope three-term joint dynamic monitoring system(hardware and software) including resistance of hydraulic supports, stress transformation between key strata and amount of key strata movement was developed. By YL-E-ZY*/65/95 small ratio hydraulic simulating supports system at core company with YL-E-DM300 point high speed linear displacement measure system and dynamic stress monitoring system, the joint dynamic monitoring system achieve the dynamic observation and automatic record of resistance of hydraulic supports, stress transformation between key strata and amount of key strata movement in the same time.The law of strata behavior of No.8203 face in Tongxin coal mine is studied by physical simulating experiment with using the three-term joint dynamic monitoring system. The result showed that the movement of overlying upper key strata may have a certain extent effect on lower key strata and strata behavior. The in-situ measurement study of No.8203 face in Tongxin coal mine confirmed the experimental result, which indicated the good practicality of the joint monitoring system. The achievement of thesis provide a new effective method to study internal link between overlying strata movement and strata behaviors, as well as the theoretical basis for strata behavior abnormal phenomena and roof control practice.