THE HYDROGEOLOGIC AND ENGINEERING CHARACTERS OF THE COAL NAPPE ROOF

This paper to put foward the classing plan and the basic Manage measures for this type of the top. Many data make clear that sliding structure broken top of the coal in Ludian can be classed the three bands,which are fault band,broken band and fissure band,from below to upper. The hydrogeologic factors of the broken top are simple and the engineering factors are complex. The broken top is difficult to manage. The stable classing conclusion applied the by four-classing plan is that the broken top only exist the three types,which are the fairly stable, instable and very instable,and the later two types are main.