Development of a 3D finite element model for shield EPB tunnelling

The results of the numerical analyses highlight the importance of modelling the above features on ground deformations and internal forces of the lining. It is shown that: (1) even moderate face pressure can appreciably reduce ground loss and prevent potential face instability in very weak ground, (2) cutterhead overcut and shield conicity have a pronounced effect of ground surface settlement which can be partly compensated by increasing the grout pressure during tail grouting and (3) a continuous shell model is a reasonable approximation of segmental lining for shallow tunnels.