The paper describes in outline the cooling water intake tunnel for Peterhead Power Station from its inception in the latter part of 1973 to its completion in 1976. The choice of site investigation, the results thereof, the design specification for the tunnel tender enquiry together with subsequent developments during the construction phase are covered.
The very weathered nature of the granite rock mass through which this tunnel was driven presented problems in interpretation of the site investigation and in the design and construction of the works which are of a fundamental nature. The more important of these aspects are dealt with in the paper.
Detailed comparisons are made between the rock as encountered in the tunnel and conditions predicted by the site investigation. Reasons are given to account for discrepancies between predicted and in situ conditions.