1) combines the basic principle of early warning with the function of GIS, constructs the theory and technology of early warning of coal and gas outburst, clarifies its connotation, studies its logical working process, and forms a complete theoretical system of early warning of coal and gas outburst.
2) By analyzing the influencing factors of coal and gas outburst, the key technology early warning model based on GIS expression is studied, and the standardized process of coal and gas outburst early warning based on GIS is put forward (Bellacicco, 2002).
3) Screening the early warning indicators of coal and gas outburst, giving the grading output standard of early warning information, and putting forward the grading output mode of early warning based on GIS.
4) Use MapX and VB6. 0 programming language, a coal and gas outburst early warning system is developed, which integrates information management and coal and gas outburst risk early warning (Zhang et al., 2006).
5) According to the regional characteristics of outburst disasters and the principle of regional early warning, the information closely related to coal and gas outburst is collected from the borehole data and historical thematic data of coal mine geological exploration, and the geological database of coal and gas outburst is established according to the specific management method of SQL Server. Do a good job of basic work for early warning of coal and gas outburst.
6) Combine the geological database of coal and gas outburst with mature mathematical geological methods of coal and gas prediction, such as multivariate statistical theory and quantitative theory; The method and steps of obtaining knowledge from the existing database by using data mining technology and establishing the early warning model of coal and gas outburst danger; Considering the abrupt characteristics of coal and gas outburst from gestation to excitation, the abrupt conditions of starting are highlighted, the early warning indicators, especially the early warning threshold, are determined, and the early warning levels and corresponding countermeasures are put forward.
7) The establishment of early warning index and comprehensive early warning model of coal and gas outburst mainly focuses on the influencing factors of coal and gas outburst time, including: natural and historical reasons affecting coal and gas outburst, such as geological structure of mine field, thickness of coal seam, failure type of coal seam and buried depth of coal seam; The realistic reasons that affect coal and gas outburst, such as mining depth, support mode, mining sequence, etc. Real-time reasons affecting coal and gas outburst: such as dynamic phenomenon during drilling, initial velocity of gas emission, gas concentration, etc.
8) According to the actual needs of coal mining enterprises, the points, lines and areas existing in the mine map are transformed into point, line and area layers representing spatial attributes in GIS technology. The early warning of coal and gas outburst based on the geographical map of coal mine is located in the second plane, and the early warning information of coal and gas outburst is highlighted in the first plane to generate the early warning map of coal and gas outburst. Through the use of GIS controls to achieve mine map management and basic GIS operation functions of mine map; Use Visual Basic6. 0 and GIS controls to develop and realize the extended functions of GIS; Use Visual Basic6. 0 and SQL Server to realize attribute data management function; Use Photoshop, Flash and other software to complete personalized functions and create a friendly user interface and human-computer interaction interface.
The design scheme of the early warning system is shown in Figure 8. 1.
Figure 8. 1 Schematic diagram of coal and gas outburst early warning system based on GIS