Research And Application On Monitoring Pressure Of Grouting Backfill Into Isolated Areas Within Overburden

The technology of grouting backfill into isolated areas within overburden is defined as grouting into overburden bed-separation through the ground inlet well to achieve the object of controlling the surface subsidence of the goaf area. Grouting pressure is the greatest factor of influencing the results of grouting backfill. Relevant personnel must immediately and accurately obtain the grouting pressure so as to efficiently monitor the process of grouting into overburden bed-separation. Therefore, this thesis mainly studies the technology of monitoring pressure of grouting backfill into isolated areas within overburden.Firstly, the process of grouting backfill into isolated areas within overburden and requirements of monitoring grouting pressure are described, and the development status of monitoring grouting pressure is analyzed comprehensively. Secondly, the characteristics and trend analysis technology of grouting pressure at various stages in the process of grouting backfill into isolated areas within overburden is investigated. Finally, a set of system for monitoring grouting pressure is designed. The system consists of the grouting pressure collection terminal, the wireless communication module and the grouting pressure monitoring terminal. The design of grouting pressure collection terminal includes the microcontroller, power circuit, A/D switching circuit and voltage stabilizing circuit. The wireless communication module is designed from the inspiration of the radio frequency chip, CC110 L, invented by the Texas Instruments, including the wireless communication circuit, PCB and software, where the software includes SPI interface communication, wireless communication protocol and data wireless sending and receiving process. The design of grouting pressure monitoring terminal mainly includes the 485 serial port bus and host computer. The King-view is adopted to design the human-computer interface. Data is received and displayed through the 485 serial port bus, and the design of the communication protocol between the single-chip microcomputer, AT89S8253, and the King-view is finished. In this system, the trend analysis function of the grouting pressure curve is designed to realize the early warning function of the grouting pressure monitoring system and ensure the normal operation of grouting backfill into isolated areas within overburden.The system of monitoring grouting pressure designed in this thesis can meet requirements of basic monitoring functions of grouting backfill into isolated areas within overburden, as well as achieve further transmission distance with the extended-range chip, to expand the application scope and have remarkable engineering value. The scalability of the system makes it have more potential applications for the development of coal mines.