Chengdu Metro Line 17(Chengdu City, Sichuan Province)

2025-12-22

NEWS

Technical Review of Slurry Pressure Balance Shield

Abstract: Slurry Pressure Balance Shield (SPB) represents a core type of closed‑face shield machine, which is widely adopted in tunnel engineering projects constructed in strata with high groundwater pressure and high permeability. This paper illustrates the working principle of SPB shields. Two major technical routes are classified according to pressure regulation modes: the direct‑control type (Japanese design) and the indirect air‑cushion control type (German design). A comparison is conducted regarding control logic, pressure stability and stratum adaptability between the two machine types. The excavation‑face stabilization mechanism governed by the coupling effect between filter cake and slurry pressure is analyzed. Technical comparison with Earth Pressure Balance (EPB) shields is also performed, providing references for shield machine type selection and construction‑technology research. 【This article is compiled for popular science purposes in the industry. Part of the technical data refers to publicly available professional literature.】

Main Composition and Technical Characteristics of Earth Pressure Balance Shield Machine

Abstract: The earth pressure balance (EPB) shield is mainstream equipment for urban tunnel construction. This article sorts out the composition and technical features of core systems of the EPB shield, including cutterhead, soil conditioning, muck‑removal conveying, grouting & sealing, guidance and monitoring. It analyzes component functions and selection points under various working conditions for industry‑wide technical exchange. 【This article is compiled for popular science purposes in the industry. Part of the technical data refers to publicly available professional literature.】