Abstract
The Rock Abrasivity Index (RAI) is a new geotechnical wear index, part of a prediction procedure for drill bit wear rate. This procedure suggests an investigation program taking into account the hole range of scale from rock mass to mineral scale. Based on the "mineral scale" and "rock scale" investigations, the RAI is calculated for relevant rock types by multipliing the rock's unconfined compressive strength and equivalent quarz content Rock mass scale information is then taken into account by use of "positive" and "negative" factors, that can either increase or decrease the drill bit lifetimes derived from the RAI prediction diagram.
Original language | English |
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Pages | 38-41 |
Number of pages | 4 |
Volume | 34 |
No | 4 |
Specialist publication | Tunnels and Tunnelling International |
State | Published - Apr 2002 |