Engineering geological investigations for the design of tunels

Abstract

This paper contains several considerations related to the engineering geological studies carried out during the design stage of tunnels.

First, a methodology for these studies is presented and, then, an analysis of the ratio cost/benefit is

discussed for the different geological and geotechnical activities, with special reference to the relative value of: a) uncored drilling together with continous recording of drilling parameters and borehole logging; and b) cored boreholes.

Finally considerations related to classification systems of rock masses and to their application in the

design of tunnels are presented.