Coal Road Support

　　my country's coal mines are mainly underground mining, and a large number of roadways need to be excavated underground. The use of roadway support to keep the roadway open and the surrounding rock stable is of great significance to the construction and production of the coal mine.

　　The basic purpose of supporting the roadway is to ease and reduce the movement of the surrounding rock, so that the section of the roadway will not be excessively reduced, and at the same time prevent the scattered and damaged surrounding rock from falling. However, the effect of roadway support depends not only on the supporting force of the support itself, but also by the nature of the surrounding rock, the mechanical properties of the support (supporting force and retractability), the installation density of the support, the time of the support installation, and the quality of the support installation. It is affected by a series of factors such as the way of contact with the surrounding rock (point contact or surface contact).

　　Generally, in order to make the roadway support play a positive role in the process of adjusting and controlling the deformation of the surrounding rock, the support should be installed before the surrounding rock is loosened and damaged, so that the support can interact with the surrounding rock while the surrounding rock is still self-supporting. It is used to bear the load together, instead of waiting for the surrounding rock to be loose, damaged, and almost completely lose its self-supporting capacity, then use the bracket to bear the weight of the fallen rock. That is to say, the support and the surrounding rock should realize the common bearing under the conditions of mutual restraint and mutual dependence.