| 摘要 |
A mine support having a ductile metal sleeve, an interior of which is filled with a first aerated cementitious material of a first density which extends over at least 60% of the axial length of the sleeve. The interior of the sleeve is also filled with a second aerated cementitious material of a second density, which is less than the first density, and which fills the remainder of the interior of the sleeve.
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