Rock mechanics review site investigation for tunnels

Tunnelling

“…follows the example of others (e.g. West et al 1981) in embracing the total process of determining the nature of the ground in respects relevant to the options for construction, while 'ground investigation' is defined as that part of 'site investigation' which entails geological and geophysical investigations commissioned expressly for the project. The progress of site investigation will generally follow the sequence set out in A practice has developed in Britain (not in Northern Ireland where borehole records are in the public domain) whereby those who have commissioned s.i.…”

“…as a percentage of cost, or as a ratio of aggregate length of borehole to length of tunnel. Thus Legget and Hatheway (1988) suggest a range of 0.3-2.0% of total cost while West et al (1981) suggest Stage II s.i. (Table 4.1) as representing 0.5-3.0% for the United Kingdom.…”