Comment by pjc50 9 years ago Ultimately you want to put passengers in the tunnel, yes? 2 comments pjc50 Reply ethbro 9 years ago From parent comment, I was guessing that the point of greatest risk would be during tunneling / initial bracing? Rather than final static bracing. pjc50 9 years ago I was thinking of the NATM failures: http://www.tunneltalk.com/images/laneCoveCollapse/Ref5-Heath...(which were during construction, but happened in "finished" sections, I believe. NATM applies a single pass of shotcrete to the cut rock surface)
ethbro 9 years ago From parent comment, I was guessing that the point of greatest risk would be during tunneling / initial bracing? Rather than final static bracing. pjc50 9 years ago I was thinking of the NATM failures: http://www.tunneltalk.com/images/laneCoveCollapse/Ref5-Heath...(which were during construction, but happened in "finished" sections, I believe. NATM applies a single pass of shotcrete to the cut rock surface)
pjc50 9 years ago I was thinking of the NATM failures: http://www.tunneltalk.com/images/laneCoveCollapse/Ref5-Heath...(which were during construction, but happened in "finished" sections, I believe. NATM applies a single pass of shotcrete to the cut rock surface)
From parent comment, I was guessing that the point of greatest risk would be during tunneling / initial bracing? Rather than final static bracing.
I was thinking of the NATM failures: http://www.tunneltalk.com/images/laneCoveCollapse/Ref5-Heath...
(which were during construction, but happened in "finished" sections, I believe. NATM applies a single pass of shotcrete to the cut rock surface)