Investigation on successive settlement due to shield tunnelling

In Japan, recent technological development in shield tunneling has made ground deformation due to shield tunneling much smaller compared with that of before the years around 1980. Especially, improvement of slurry shield and earth pressure balanced shield (E.P.B.) and also development of simultaneous backfill grouting contribute to repression of ground deformation under an eminent construction control. However, it is known that successive settlement after a shield passed away remains large in excavation of soft clayey ground even now. It is important to study the mechanism of successive settlement due to shield tunneling in order to predict and reduce the settlement. For this purpose, many case records were analyzed on successive settlement and we got a interesting conclusion that the successive settlement is depend on the degree of disturbance and soil types.