Authors: Davison, GR; Fuller, PG


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Davison, GR & Fuller, PG 2013, 'Investigation of expanding Split Sets', in Y Potvin & B Brady (eds), Ground Support 2013: Proceedings of the Seventh International Symposium on Ground Support in Mining and Underground Construction, Australian Centre for Geomechanics, Perth, pp. 163-170,

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Expanding rockbolts anchor to the rock mass using friction and mechanical interlocking at the rockbolt interface. An internally expanding friction rockbolt is capable of generating much higher radial force along its entire length than standard friction bolts. This results in increased friction between the rock mass and the friction bolt. Tubular form expanding friction bolts have never gained a following in Australia due to perceived installation issues, relatively low tensile strength and corrosion problems associated with the thin expansion walls. This paper shows that Jumbo installation of expanding friction rockbolts is now possible with the same ease as traditional ‘Split Set’ style friction bolts. The expanding friction bolt discussed in this paper has the same material properties as conventional friction bolts, but provides increased corrosion protection and increased anchorage capacity per embedded metre due to the expanding properties of its grout core.

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