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(11) | EP 0 142 280 A3 |
| (12) | EUROPEAN PATENT APPLICATION |
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| (54) | Elongate mine support |
| (57) An elongate mine support comprising a timber pole (2) with a metal sleeve (3) reinforcement
therearound has circumferential weaknesses (4) in the sleeve for assisting controlled
collapse of the sleeve when the support is under axial load. The circumferential weaknesses
may be formed between the adjacent edges of separate sleeves (29) (see Figure 6).
The separate sleeves (35) (see Figure 7) may each be belled at its lower end so as
to slip each one over the next lower sleeve during a controlled collapse of the support.
The weaknesses (8) (see Figure 2) may be spirally formed and so as to be capable of
being torn off (see Figure 4) to assist in shortening the support. The weaknesses
(44) (see Figure 8) or (52) (see Figure 9) may be formed as corrugations. |