Abstract
Recently, flat cross section tunnels have often been adopted on NATM. This tunnel is also a flat cross section tunnel. And Standard combinations of tunnel supports are adopted. It seems, however, that behavior of flat cross section tunnel is different from that of circle cross section tunnel.
Therefore using the results of measurement A (routine observations and measurements) and measurement B (measurements to be supplemented according to the ground condition), the authors grasped the characteristics of behavior of flat cross section tunnel.
