Abstract: In shoring a mine tunnel, use is made of a plurality of panels 11 each comprising a rectangular member with detents 15 formed in two opposed edges. The panel 11 may be composed entirely of sheet metal or may comprise spaced-apart rectangular or strips of sheet metal, with spaces between occupied by wire or rod mesh. The detents may comprise U-shaped tongues 18 defined by a C-shaped slot 16 and a T-shaped slot 17 the tongues acting in a hook like manner to interconnect the detents 15 on the superimposed edges of adjacent panels 11. Where the panel 11 is entirely of sheet metal, apertures 25 may be provided along the other pair of opposed sides for engagement of links such as 58; where the panel is partly of mesh such links can be looped through the mesh.

Abstract: There is disclosed a rail sleeper which when secured to rails affords rapid disengagement when necessary and is comprised of a metal bar of a U-shaped channel section. At two locations along the length of the bar portions of flanges of the sleeper are removed to provide slots disposed at right angles to the longitudinal axis of the bar. Each slot is wider than the base of the rail fitting thereinto with the space between slots dependent upon the gage between parallel rails and with the depth of such slots being varied to suit rail height. One rail flange is secured in place by an overhanging portion of the sleeper flanges. The other rail flange is secured by a generally T-shaped steel plate which is bolted to the bottom of the U-shaped channel section such that the horizontal bar of the T-shaped plate rests across the upright flanges of the sleeper. One edge of the horizontal bar engages the web of the rail and the other edge engages the edge of the slot, thus wedging the rail into secure engagement.