Abstract:

The construction technology of mountain tunnel in China is underdeveloped. Hence, the mechanized construction method for large crosssectional tunnel on highspeed railway is introduced. A new kind of tunnel construction organization mode with four tunnel construction lines, i.e. excavation, support, lining and water cable channel, is developed based on a suit of tunnel mechanized construction equipment and field test, so as to realize the continuous construction of large crosssectional tunnels in Grade Ⅳ and Ⅴ surrounding rocks. A series of problems, i.e. accurate positioning of excavation blasting holes, accurate installation of system anchor bolt and simultaneous uploading of construction information, have been solved by automatic tripleboom rock drilling jumbo. The cycling time of each construction process has been shortened, and the safe management of early closure of weak surrounding rock has been realized by configuration and application of largescale equipment with high power. The monitoring data and applicable results show that the construction quality of mechanized construction method for large crosssectional tunnel is feasible and safe, and the construction efficiency is high.

Key words: highspeed railway tunnel, weak surrounding rock, mechanization, large crosssection excavation, stability of surrounding rock, advance prereinforcement