关键词: 黏性地层, 盾构刀盘堵塞, 界面降黏, 电渗透技术, 化学改良技术, 电-化协同, 有效能耗, 尺寸效应

Abstract: During shield tunneling through cohesive ground, mud-cake formation on the cutterhead readily occurs, leading to excavation hindrance and severely constraining tunneling efficiency. To address the instability of anti-adhesion measures in field applications, this study proposes an electro-osmosis-chemical modification synergistic approach to reduce clay adhesiveness. It further investigates the effects of key control parameters on de-adhesion performance and energy consumption, and evaluates its engineering-scale applicability and optimal parameter ranges. Inclined-plane tests and pore-water migration experiments are conducted under varying voltages, mud-cake thicknesses, and modifier dosages. An equivalent-scale numerical model (cross-sectional diameter of 6.88 m and thickness of 1.5 m) is developed to simulate and analyze the electrochemical synergistic de-adhesion process. The results indicate the following: (1) De-adhesion performance increases with increasing voltage but decreases with increasing mud-cake thickness at a given voltage. (2) Under laboratory conditions, a favorable balance between de-adhesion performance and energy consumption is achieved when the mud-cake thickness is 20 mm, the modifier dosage is 3%, and the applied voltage is 5 V. (3) Numerical simulations show that under low-voltage conditions, the de-adhesion rate is slow, and the overall effectiveness is limited. As the voltage increases, both the de-adhesion rate and the affected zone increase markedly, whereas the incremental gains gradually diminish in the highvoltage regime. (4) Incorporating the soilconditioning agent markedly expands the effective influence zone of electro-osmotic de-adhesion. Under the equivalent-scale numerical model, the overall electrochemical synergistic de-adhesion performance is optimal at 20 V with a 3% modifier dosage. In summary, the electrochemical synergistic de-adhesion approach effectively enhances the anti-adhesion performance at the cutterhead-clay interface. For engineering applications, the voltage and modifier formulation should be optimized by jointly considering energy consumption, ground conditions, and equipment constraints to optimize the de-adhesion performance and tunneling efficiency.

Key words: clayey strata, shield cutterhead clogging, interface de-adhesion, electro-osmosis, chemical conditioning, electrochemical synergistic technique, effective energy consumption, scale effect