Seery, J & Lapwood, J 2007, 'Use of an Excavation Compliance Indicator to Assess Conformance to Slope Design', in Y Potvin (ed.), Proceedings of the 2007 International Symposium on Rock Slope Stability in Open Pit Mining and Civil Engineering
, Australian Centre for Geomechanics, Perth, pp. 431-437.
The compilation of factors associated with the construction of a slope has been collectively termed the
excavation compliance indicator. The excavation compliance indicator is a tool that can be used to quantify
the adherence to slope design in the operational mine environment. It is the collection of measurements
pertaining directly to batter face angle and berm width and indirectly to the inter-ramp angle. The
characteristics are measured from mine survey as-built pickups and Sirovision triangulations which have
been imported into Maptek Vulcan. The characteristics are compared directly to the design batter face
angle, berm width and inter-ramp angle.
To date, the excavation compliance indicator process has been undertaken on a number of pits in the West
Pilbara Mine Operations at Pilbara Iron. The aim of undertaking this analysis is to assess the quality of
excavation of slope angles and construction of berms to check conformance to design slope parameters.
In the analysis of mine survey as-built pickup data for the Tom Price South East Prongs pit, the as-built
batter face angle was found to be on average 4 degrees lower than design batter face angle. It was found
that in general, the average as-built batter face angle for the mine survey pickup was no more than 2 degrees
lower than the interpreted Sirovision model batter face angle.
This work will help to drive the reconciliation process between the geotechnical design parameters and
actual excavation performance. There is a direct correlation of the excavation compliance indicator to the
drill and blast design and the final wall excavation process.
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India. International Journal of Rock Mechanics and Mining Sciences. Elsevier.
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Rajasthan, India. Engineering Geology 53 pp, 47-55. Elsevier Science.
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case study. Proceedings 39th symposium on engineering geology and geotechnical engineering: research to
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