Grouting reinforcement technique is a common method to avoid the risks of collapse or water and mud inrush. However, the sealing efficiency of grouting subsea tunnel in different groundwater environment remain unclear. In this study, experimental investigation of grouting under groundwater environment was conducted to study the various factors on the sealing efficiency under groundwater environment, including potential of hydrogen and initial flow speed. The experimental results show that the sealing efficiency of superfine cement grout gradually weakens in both acidic and alkaline environments. Within the initial flow speed range of 0.1 m/s to 1.0 m/s, the grout retention ratio (GRR) decreases progressively as the flow speed increases. Notably, the superfine cement-sodium silicate grout exhibits excellent resistance to groundwater scouring. It further proposes a practical grout material selection principle tailored for water and mud inrush, which is validated through the Haicang subsea tunnel, bridging the gap between laboratory research and engineering application. This principle not only resolves resource waste caused by grouting loss but also provides a direct, actionable guide for future subsea tunnel grouting projects.
Zhou et al. (Tue,) studied this question.