Abstract:

The interaction between the cutterhead and the soil mass is very complicated during excavation in shield tunneling. In the paper, nonlinear dynamic models of cutterhead excavating in sandy soil strata and clay strata are established by using the finite element analysis software ABAQUS, and the yield and failure of the soil mass are simulated according to DruckerPrager plastic yield criterion and by using the progressive damage and failure rules containing element deleting function. The results showed that: 1) During excavation, the soil mass accumulates its plastic strain until failure; 2) The excavation load of the cutterhead changes periodically; 3) The axial force and moment of the cutterhead when excavating in sandy soil is larger than those when excavating in clay; 4) The cutting efficiency of the cutterhead when excavating in sandy soil is lower than that when excavating in clay. The study results can provide theoretical guidance for the design of the cutterhead of earth pressure balanced shield.

Key words: shield, cutterhead, finite element, dynamic simulation