Research On Bolting With Wire Mesh Support Technology Of Composite Roof In 9113 Working Face Of Linhuan Coal Mine

The composite roof roadway of the middle group coal seam in Huaibei mining area is common.The number of roof layers is large and the thickness is thin,and it also contains weak interlayer.The surrounding rock of the roadway is easily affected by the stress redistribution,and it is easy to form a separation layer and a roof.It is difficult to form a stable bearing structure.Roadway support problems constrain the sustainable development of the Huaibei mining area.This paper takes the 9113 working face roadway of Linhuan coal Mine as the research object,and systematically analyzes the deformation and failure characteristics and causes of the original U-shaped steel shed support through field investigation,laboratory test,numerical simulation,theoretical analysis and on-site measurement.Different bolting with wire mesh support schemes are proposed for different conditions,and industrial tests are carried out on site.The main research contents and results of this paper are as follows:?1?In-depth field investigation,collecting and arranging the deformation and failure characteristics of surrounding rock of the original U-shaped steel shed roadway and supporting conditions,and obtaining that the U-shaped steel bearing capacity is incompatible with the surrounding rock deformation and failure law of the composite roof roadway is U-shaped steel shed The root cause of deformation and damage was protected,and laboratory tests were carried out on the roof rock of the roadway.The basic physical and mechanical parameters of the roof rock layer of the roadway were measured.The research results show that the 913 working face roadway of Linhuan Mine is a typical composite roof roadway.The rock layers of the roadway roof are thin and varied,and contain weak interlayers,which have certain uniqueness.?2?Because the composite roof rock layer contains weak interlayer,in order to explore the influencing factors of the anchor roof support of the composite roof roadway,the FLAC^3D numerical simulation is used to compare the presence or absence of the weak interlayer and the different weak interlayer layers.The results show that the weak interlayer is The anchorage zone edge has the greatest influence on the bolt support,while the weak interlayer has the same influence on the bolt support in the anchor anchorage zone and outside the anchorage anchorage zone,and the weak interlayer is in the anchorage anchorage zone.The external influence is slightly larger than the anchor anchorage area.?3?According to the results of numerical simulation,combined with the idea of classification support for different roof conditions of different roadways,two different support schemes are proposed to correspond to whether the weak interlayer is at the edge of the anchorage zone of the bolt and by numerical simulation.The effects of different support schemes under different conditions are analyzed.The results show that the"high-strength prestressed anchor cable support technology"scheme is not enough to control the deformation and damage of the roadway,and the"high-strength prestressed anchor cable+structure compensation anchor rod support"The protection technology scheme can effectively control the weak interlayer at the edge of the anchor anchorage zone.?4?According to the research results,industrial tests were carried out on site,and different support schemes were adopted for different conditions on the site by means of classified support.When the weak interlayer is located in the anchorage section of the anchor,the support scheme with the anchor cable as the main body is adopted;when the weak interlayer is located at the free section of the anchor and outside the anchorage area of the anchor,the support scheme with the anchor as the main body is adopted.The results of three sections on the site show that the two support schemes effectively control the deformation of the surrounding rock of the roadway and achieve good support.