Traditionally, closure criteria and control of grouting effectiveness for bedrock permeation grouting has always relied on "final stage" confirmatory water pressure testing of the grouted rock mass using classic Lugeon-style testing. However, increasing industry-wide acceptance of real-time grout monitoring using electronic data acquisition can allow adoption of closure criteria using grouting data alone, without recourse to additional water pressure testing. This use of electronic data is facilitated by three other advances: grout stability and properties (rheology); understanding of grout penetration; and monitoring technology to control grout injection. Drawing upon these advances, and supported by modelling of grout flow in fractured rock (presented as a companion paper, Carter et. al., 2012), procedures are proposed to allow reliable rock grout curtain construction using cement-based grouts.

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As part of a power plant expansion project at the Diavik DiamondMine in the Northwest Territories of Canada, forty eight (48) rock anchors for six (6) exhaust stack foundations were designed, installed and pull-tested. The Diavik Diamond Mine is located in a region of continuous permafrost which presents unique challenges for design and construction. In particular, frozen bedrock is known to slow the curing time of grout, and if incorrectly cured, significantly reduce the strength of the cured grout. In an effort to accurately replicate the in-situ ground temperature conditions while curing grout samples, single node thermistors were installed to monitor ground temperatures and the samples of the cold weather anchor grout were cured in a calcium chloride ice-bath.The anchor installation procedure, cold weather anchor grout formulation, in-situ ground temperature measurements, unconfined compressive strength (UCS) test results of the ice-bath cured grout and a summary of the anchor pull-test results are presented.

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