Key technologies for design and construction of shield tunnels in pebble stratum immersed in water 并列题名：Key technologies for design and construction of shield tunnels in pebble stratum immersed in water Key technologies for construction of expressway tunnels in mountainous areas Key technologies for mechanized construction of high-speed pailway tunnels Key technologies of design and construction for special-shaped large-long-deep foundation pit in Ningbo rail transit New technology of design and construction for steel pipe-jacking Key technology of design and construction for cast-in-cantilever concrete arch bridge