CHANNEL TUNNEL END IN SIGHT

This article discusses recent progress in the construction of the Channel Tunnel. Since the initial undersea breakthrough in December 1990 and the completion of the service tunnel in January 1991, the remaining tunnel boring machines have been busy breaking their own records. During the month of March 1991 alone, the four closing marine running tunnel machines completed more than 5.5km. The completion process for the Running Tunnel North started in late April 1991, and for Running Tunnel South a month later. Practical construction of all driven tunnels was expected to be complete nearly half a year ahead of schedule. The UK undersea crossover chamber received its permanent lining of unreinforced concrete, between 900mm and 1200mm thick; the end walls are made of 3.5m thick reinforced concrete. The French are using new methods in the construction of their crossover cavern, the large major civil engineering job on the Channel Tunnel project. Work is progressing well on both the UK and French Terminals, with the construction of overbridges, platforms, permanent buildings, access and egress roads, and tracklaying all well advanced with prospects of completion by the end of 1991.