A method of tunnel construction known as NATM is changing the game (video)

Enter PORR Tunnelbau an Austrian drill and blast tunneling company with more than 100 years, which never ceases to develop novel tunneling methods and techniques such a New Austrian Tunneling Method known as NATM.

For PORR Tunnelbau, progress is the result of experience with the continuous practice. Today, NATM is an international recognized method of tunnel construction that’s changing the tunnel construction game.

Source

https://www.youtube.com/watch?v=GMFo1fN_Exk