Underground Singapore 2011 stored on site for too long, despite the storage environment being controlled. Microfine grout from a potential alternative supplier was also tested, and found to have poor penetration properties in comparison with that used. 6. CONCLUSIONS The grouting test mixes and grouting trial at Bukit Panjang Station were carried out to assess what changes needed to be made to typical rock grouting practice, as applied in Sweden, in the very different climatic conditions in Singapore. The different climatic conditions had a very significant effect on the grouts, and major adjustments to the planned grout mix and mixing process had to be made to achieve practicable grouts. Routine testing of the grouts during the trial and subsequently during injection was necessary to verify that they had, and continued to have, the required properties. Due to the initial inexperience of the workforce, changes to simple working procedures, such as the standard and methods for cleaning of the mixing equipment had to be made, in order to ensure grout quality. The regular Quality Assurance testing of the grout was a key factor in identifying the need for changes to procedures. REFERENCES Bruce D.A. (2011). Rock grouting for Dams and the Need to fight Regressive Thinking. Geotechnical News, vol 29, Number 2, June 2011, pp 36 to 43 Defence, Science and Technology Agency (2009). Geology of Singapore, 2 nd Edition AECOM (2008). Geotechnical interpretative Report for Contract 912, Rev C.
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