| 摘要 |
An arched roof support for a mine opening essentially includes an elastic plate member with a preselected curvature across its length employed for establishing a prestressed emplacement into a load-bearing contact along the middle portion of the roof stratum of the mine opening. The material forming the plate member is selected for withstanding an elastic deformation force to maintain the prestressed emplacement which is effected by the elevated support of one or both sides of the plate member along or toward side ribs of the mine opening. As anchoring means, the side edges of the plate member are either supported solely by the ribs of the mine opening or additional support is supplied by roof bolts, rib bolts or props having an adjustable length. A hydraulic or mechanical actuator is used to elevate one or both side edges of the plate member to its emplacement elevation whereby the side edges have been raised to between two-thirds to three-quarters of the height of the mine opening or at the roof surface. In a further embodiment, roof bolts are used solely for the prestressed emplacement of an elastic plate member onto the roof stratum or side rib. The pre-formed shape of the elastic arched plate is parabolic, elliptical or a combination of convex and concave configurations. Apparatus for producing the pre-formed shape of the plate is disclosed as well as various forms of anchor means and support props.
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