ABSTRACT
Investigation of the prior stage of mountain tunnel with long length and high overburden was conducted for the purpose of clarifying each following item.
• The overall geological structure, distribution of geological features and characteristics of the tunnel section
• Ground classification with synthetic technical consideration based on the results of investigation
• Topography and geology of portal locations, basic data for a problem and its measure design, and
• Basic data for evaluation of face stability, design of support, selection of auxiliary method, selection of excavation method and tunnel driving method
Especially in a tunnel design stage, geographical and geological data of high accuracy are required.
