Discussion. The Thames-Lee Tunnel Water Main.

Tunnelling

“…For this purpose, the most satisfactory method for small diameter tunnels entailed the use of tapered segments so that the ring was expanded by driving such segments into the ring by the use of the propelling jacks of the shield. The Don-Seg lining (Figure 1.3) was first used for the Lee Valley-Hampton water tunnels following their successful use in an experimental tunnel in 1951 (Scott 1952, Cuthbert andWood 1962). The improved rates of construction achieved by the several innovations are illustrated by Table 1.1.…”