Construction and utilization of rock caverns in Singapore .1. The Bukit Timah granite bedrock resource

The Bukit Timah granite underlaying central and northern Singapore has been studied for the feasibility of hosting large unsupported rock caverns. Detailed geological investigation, comprising mapping, seismic refraction and electrical resistivity surveys, deep vertical and inclined drilling, conventional and geophysical borehole logging and in-situ hydraulic testing (at a selected location), as well as laboratory testing, have been performed. The results indicate that the granite is of extremely good quality and suitable for the construction of large unsupported caverns. Therefore, the Bukit Timah granite should be considered as a valuable resource for cavern and underground space development in Singapore.