Figure 8.
The diagram displays the original design tunnel position and the modified tunnel position with a one millimetre zone of influence extent. It indicates the ground level at one hundred five point eight metres A T D, along with the modified tunnel position at seventy-one point one metres A T D, where the primary lining invert level is located. The D C O limits of deviation are marked at twenty-eight point five metres. A measurement of ten point fifteen metres is annotated between the two tunnel positions. Angles, indicated by a forty-six degree marker, and blue and red dashed lines specify the original and modified tunnel extents. Additional details such as symbols or arrows may indicate directions or connections relevant to the tunnel structure.Hammersmith Bridge, main tunnel deviation