Recorded settlements from the DLR tunnels to Bank

The prediction of ground settlement due to tunnel construction is now a necessary part of the design function. Whilst reasonable predictions of surface settlement can be made, the prediction of building settlement, especially those with deep foundations and underground structures is more difficult. Using the accepted method of prediction at the surface by lowering the surface to foundation level exaggerates the prediction and pre-supposes that the building will settle more than the ground surface. Whilst the monitoring results described in these pages were for a specific reason i.e. to predict the effects on existing tunnels, the results together with additional data recorded on the Jubilee Line construction in the 1970's have been used to derive a formula for the prediction of ground settlement at all levels and is described by Heath & West (1996).