Structure And Stablity Influencing Factors Of Coal 3RD Roof In Longgu Mine Of Juye Coalfield

This paper provides systematic analysis for lithology composition characteristics of coal roof, geological property and rock mechanics property of coal 3th seam's roof by using sedimentology, petrology, Tectonic Stratigraphy and structure of rock mass-rock mechanics, with Longgu coalfield in Juye mine as an example. A stability analysis scheme is concluded for coal 3th seam's roof; and a new method for evaluate and forecast the coal roof stability is discussed here.Use sedimentology and stratigraphy technology to analyze lithology distribution, sediment sequence and structure of coal roof. Five types of coal roof are concluded: coal-thick bedded sandstone (main roof), siltstone-thick bedded sandstone, mud rock-siltstone-thick bedded sandstone, siltstone-mud rock-thick bedded sandstone and mud rock-thick bedded sandstone.Analyze the coal roof structure, especially minor faults in details. This method can be used together with coal roof structure-strata analysis method (such as competent strata effect) to provide more detailed parameters. The coal roof under research can be divided into five levels: stable, relative stable, medium, less stable; unstable.Study the lithology property of coal roof, strata structure, sediment change rules, influence of underground water, relation between strata and overall mechanical effect. A distribution rule about anti-pressure intensity of coal roof stones is concluded and the rock division based on stability is determined.The analysis to factors that may affect coal roof stability decides the correlation among them. On top of that, the BP artificial neural network model is used for quantitative forecast. The system forecasts the coal 3th seam's roof stability in the first mining area and puts forward the evaluation result.