Method for controlling caving of roof of short distance coal bed roadway

Abstract

The invention discloses a method for controlling caving of a roof of a short distance coal bed roadway. The method comprises steps as follows: 1, determination of basic mechanical parameters of surrounding rock; 2, determination of reserved excavated volumes of two sides of a roadway; 3, excavation of the roadway; 4, determination of a roadway side part supporting structure: a roadway support structure comprises roadway support units and grouting anchor rods which are arranged in a staggered manner, and each roadway side part support unit comprises a roof support system and a roadway side part support system; 4, determination of the vector height of extreme caving arches; 5, determination of the roadway support structure; 6, support construction of roadway surrounding rock; 7, excavation of the next section and support construction of the roadway surrounding rock; 8, completion of the construction process of the short distance coal bed roadway after repeated implementation of the step 7. The method adopts simple steps and is reasonable in design, convenient to implement and good in use effect; the reserved excavated volumes of two sides of the roadway are determined according to the surrounding rock deformation condition of the short distance coal bed roadway respectively, and the roadway side parts and the roof are supported through matching of the grouting anchor rods and the roadway support units.

Description

technical field [0001] The invention belongs to the technical field of roadway construction, and in particular relates to a method for preventing and preventing the roof caving of a roadway in a short-distance coal seam. Background technique [0002] In recent years, with the gradual depletion of medium-thick coal seam resources, the mining of short-distance thin coal seam groups (also known as short-distance coal seam mining) has become one of the inevitable trends in the development of coal resources today. It is generally considered that the distance between coal seams is very close, and the coal seam has significant mutual influence during mining; generally refers to the coal seam whose distance between coal seams is less than 30m. Due to the small distance between coal seams in close coal seams, affected by the concentrated pressure formed by the coal pillars left behind after mining the upper coal seam, the surrounding rock deformation is severe. The large amount of d...

AI Technical Summary

Problems solved by technology

Practice shows that the basic theory of Platts' caving arch reflects the objective law of ground pressure to a certain extent, but it still has the following deficiencies: First, the horizontal stress σ h The impact on the caving arch, in fact, the lateral pressure coefficient λ has an influence on the shape and sagittal height of the roof caving arch; second, the simplification of the form of the two sides is improper, and the form of the rib has a greater impact on the sagittal height of the caving arch. Third, the shape of the roof caving arch is too simplified when the two sides are stable; fourth, the influence of the wedge-shaped failure of the two sides on the roof caving arch height is neglected. The arch sagittal height of this form is lower than the theoretical value

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