Numerical Simulation Study On Cutting Process Of Shield Cutterhead

Since twenty-first Century,with the increasing shortage of urban land resources,more and more experts and scholars turn their attention to the development of underground space resources.Shield method is widely used in all kinds of tunnel engineering because of its small influence on the ground environment,high construction safety,fast construction efficiency and little influence on weather conditions.Shield cutter type should be selected according to the geological conditions,namely,choose the type of cutter in different cutting different soil,so the soil cutting process of shield cutter has the important reference significance for design of shield cutter.Firstly,through the theoretical research on the parameters of shield tunneling system and the mechanical properties of soil,the constitutive model of soil is deeply discussed.Using the extended Drucker-Prager constitutive model and the damage model with the function of removing the unit,the model can correctly reflect the cutting process of the soil,and simulate the material properties of the soil.Secondly,the 3D model of cutter and soil is established by using 3D software.According to the characteristics of dynamic contact,analysis and Simulation of grid partition model using the finite element software,numerical simulation of cutting process under different working conditions of the cutter,the cutter load variation under different working conditions and cutting load with the change of time is obtained,provide a reference for the structure design of cutter.Finally,according to the empirical formula,the thrust and torque of the shield are calculated,and the corresponding load is loaded.Through the establishment of 3D model of cutterhead cutting soil,carries on the simulation analysis of the soil cutting process of shield cutter,the cutter deformation variation and cutter under different loads and different driving speed is obtained,pointed out that the weak parts of the structure design of cutterhead.According to the optimization of the opening rate and the connection between the cutter and the bracket,the structural optimization design of the cutterhead is obtained,provided reference for optimization design of shield machine cutter.