Tunnel roof support is a kind of passive support for coal mine support, with high tensile strength and compressive strength, as well as good toughness. The composition of the tunnel roof support includes: three sections of U-shaped steel, four carlans, side shed parts, and bottom corner plates.
The tunnel roof support are arc-shaped, and the number of them depends on the size of the roadway section, the support force, and the transportation conditions. There are three types of column legs, one is the upper part is a circular arc, the lower part is a straight section; the second is all curved, and there is only one radius of curvature; the third is all curved, but has two curvatures radius. A base is welded under the column legs supported on the top of the tunnel. The size of the base depends on the hardness of the base. The tunnel roof support connector is a clamping device between the bracket section and the inter-section, which can play the role of inter-section connection. It can also partially compress the connected two section steel joints to provide pre-tightening force and make the tunnel roof support friction Therefore, the arched support has a certain working resistance and a certain amount of shrinkage. The function of the tie rods between the frames is to enhance the relative stability of the whole bracket, and to connect the brackets longitudinally to form a whole. The backing material is the filling material between the tunnel roof support and the surrounding rock. The purpose is to make the tunnel roof support close contact with the surrounding rock, improve the stress condition of the support, increase its bearing capacity and maintain the stability of the surrounding rock.
The tunnel roof supports high supporting force, strong supporting strength, and can be used many times. It is widely used in mines, especially in deep complex roadways and soft coal seam roadways.
