The Multilayer Wedge Method for Estimating TBM Face Pressures in Stratified Soils

摘要

The current tendency toward ever-larger TBMs is accompanied by a higher probability ofrnsignificant mixed-face conditions. The unprecedented 17.45 m diameter earth pressure balance TBM for thernAlaskan Way Viaduct Replacement Program (AWVRP) is a contemporary example. The TBM is being drivenrnthrough complexly layered glacial sands and clays, wherein several alternating soil units may comprise therntunnel face. Analyzing the required TBM face pressure under such conditions is a non-trivial task and has beenrnfacilitated by the recently developed multilayer wedge method (MWM) (Hu et al., 2012). This paper introducesrnkey aspects of the MWM and its application at the AWVRP. Results obtained with the MWM are compared tornclassical methods for predicting required face pressure.