Special Grout for Rock Consolidation: DSI Australia supplies the Pajingo Gold Mine with DYWI® Grout
In December 2015, the Jandam 700 Grouted Sill Pillar Project commenced at the Pajingo Gold Mine. The mine, which is operated by Evolution Mining, is located in Queensland in northeastern Australia. For this project, the pillars that had been left to support the mined drifts underground had to be consolidated using grout in order to ensure the stability of the galleries and permit future excavation work.
After several months of negotiations, DSI Australia was awarded a contract for grout supply thanks to the professional proposal put forward by the Ground Consolidation Team. For this project, DSI supplied 200 x 1,200kg bulker bags of DYWI® HY Grout, which is a high yield, low strength product that can be mixed at different water to powder ratios, producing different yield factors.
DSI also assisted with the installation of the special grout and formed a Joint Venture with Bolt Up Mining, who provided 4 employees (2 per shift) to carry out the work on site.
The plan was to grout the Jandam 700 pillar from below at the Jandam 685 level using the special grout. The process included drilling SDA rods from below through the roof and into the pillar to be consolidated. The lengths of the SDS hollow rods were extended to 10m using couplers. Afterwards, the DYWI® HY Grout was pumped up through the strata to percolate down through the lose fill for consolidation and strengthening.
28 days later – after the complete curing strengths were achieved – the strata below was scaled out to recover an old high grade ore body.
This project is extremely relevant to DSI Australia due to the fact that it is the first large scale grout supply and application project for the company. It therefore also demonstrates the widening of DSI’s business activities in injection chemicals. In this area, DSI offers high quality special grouts and resins that are used for underground rock consolidation. The special grouts specifically designed for mining are produced in Australia and can be provided in 20kg and 1,200kg bags.