Yielding arch support for mine roadways - has stay width tapered from flange end to rounded head end and adjoining overlapped segments

摘要

Yielding arch supports for mine roadways consists of tee segments placed with their flanges alternately inside and outside and held together where overlapped by turn-buckles. The free end of the stay forms a head rounded at the side and thus wider than the stay where it joins the flange but narrower than the segment foot. The stay width changes steadily from the flange (5) downward so that adjoining segments when overlapped make continuing contact from flange down to head end (3). The curvature (r4) of the rounded sides (4) of the head (3) equals the curvature (r5) at the flange end of the stay (5). Pref. the sectional width of the stay should increase rectilinear from flange to head end. It is possible to incorporate a circular thickened part in the stay, halfway between flange and head ends, and approximately the same section as the head.