Abstract: With the help of ABAQUS FEM software, a numerical study is carried out on the mechanical properties of bent bolted connection in shield tunnel under the effect of preload, which offers theoretical evidence for the design and construction of bolted connection, considering the DP constitutive model fit for concrete as well as the plastic constitutive model fit for steel. The differences between the effect of preload under different load cases are analyzed, and the principle of the preload effect is revealed. The results show that the preload can improve the structural behavior of bent bolted connection, the restraint on the segment increases, and the entire deformation decreases.