partial pressure joint arch tunnel
Asymmetrically-loaded Double-arch Tunnel
double lines multi-arch tunnel
Double Multi-arch Tunnel
DOUBLE-ARCH TUNNEL
双连拱
联拱隧道
双联拱隧道
连拱隧道
双连拱隧道
双跨连拱隧道
landslide caused by twin-arch tunnel
Large Span and Double-arch Tunnel