| 摘要 |
The tunnel (14-16), especially for road traffic, is made of rectangular-section prefabricated bodies (13) which may be transported to site and dovetailed together. The tunnel bodies incorporate nuts (17) connected to wires or rods (18) suspended from overhead portions (11) of portal frames (10), and may be lowered one- by-one into a trough excavated between two retaining sheet piling walls (2). There are stiffening frames (3) between the walls. The trough (6) may be excavated to below the water table (5) and concrete may be poured in to make the floor (20) onto which the tunnel bodies may be lowered.
|
