| A new construction mrthod by laser excavation is studied．First，the fundamental experiments were Conducted for investigating the interation between rocks and lasers．Next，some parts of lasers were improved．[*]Two beams generated by the YAG laser system are coupled to gain the 6kw beam．This is applied through a long focus lens on the rock excavated from the similar place in which the large-scale rock failure occurred．10-minitu irradiation produced a small hole of 230mm depth and 20mm in diamater．The same experiment is Achieved out of doors to demonstrate laser boring has a practical use． |
