6.1 Shield Gravel Formation Long Distance Boring T...
In the construction of urban rail transit projects，shield method is a widely used construction technology.Sandy soil has the characteristics of small cohesion，large internal friction angle，poor flow plasticity and large permeability coefficient.When shield tunneling in sandy stratum，it is prone to wear of cutter head，cutter and screw conveyor，increase of torque and thrust of cutter head，abnormal tunneling parameters，difficult excavation and difficult control of land subsidence.Serious accidents will occur.In recent years，more and more attention has been paid to the problems caused by shield tunneling in sandy strata，especially long distance tunneling.
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J.Chen et al.，Construction Technology of Large Diameter Underwater Shield Tunnel，Key Technologies for Tunnel Construction under Complex Geological and Environmental Conditions，https://doi.org/10.1007/978-981-16-5896-9_6