1. Introduction . In recent decades, shield construction has become a developed construction technology [ 1 ]. Currently, shield construction is widely used in soft soil tunnel constructions, such as saturated soft clay, silty soft soil, saturated sandy silt, and silty sand. In shield construction, by injecting grout to fill the gap between the pipe wall and the ground, the formation loss can be effectively reduced. Grouting reduces ground subsidence and prevents the penetration of ground ...