Mechanical Analysis And Inverse Identification On Load Of Shield Tunneling Machine

Shield tunneling machine is typical tunneling equipment widely used in tunnelsand underground engineering with characteristics of complex structure, huge size andload. Driving load is the core mechanical parameters of shield machine. Analysis andmodeling of load are important theoretical foundation of shield design and excavation,and it is also the guarantee of fast, safe and efficient construction.Load estimation and calculation are the key technologies of shield design andtunnel construction, while they are also the nodus of research on shield machine. Theinfluences of operation parameters of shield machine are analyzed firstly and coreparameters of load are determined. Dimensional analysis is carried out to study themajor factors and characters influencing the load based on the mechanical analysisduring the excavation. Basic framework of load mechanical model is established byexamining the combination pattern of these factors and characters. The model enablesthe mechanical descriptions among the key factors of operating conditions, geologicalconditions and equipment structure. Also, specific energy (SE) model is deducedbased on the analysis results of this model.With on-site data of Tianjin No.9subway, non-dimension coefficients areidentified by ridge regression method. Inverse identification model of load andspecific energy are established via mechanical analysis, dimensional analysis and datamining. Then the identification results by mechanical model and PSO-SVM methodare compared. The effect of mechanical model residual is discussed and accuracycompensation and dynamical forecasting of mechanical model are achieved.Mechanical model of load and SE are further applied in subway projects withdifferent geological conditions of Tianjin, Beijing and Shenzhen. The optimizationrange of penetration in different subway projects are discussed, and the effectivenessand feasibility of mechanical and SE model are verified.