Tunnel excavation method using a blasting rock classification

摘要

PURPOSE: An NATM using a probe large hole burn out bedrock classification system is provided to restrain the damage of the in-situ ground maximally, to reduce explosives by preventing overcharge and to improve blasting and digging efficiencies. CONSTITUTION: The NATM(New Austrian Tunneling method) using a probe large hole burn out bedrock classification system comprises the steps of: dividing the section of a tunnel into a large hole part(1) and a perimeter part(2), then boring; charging the large hole part(1), then blasting; and tunneling by utilizing the extended state of a plastic region occurring on the perimeter part(2) by the blasting result of the large hole part(1) for measurement.