A Numerical Investigation on Reducing the Effects of Deep Excavation on Adjacent Metro Lines Using Jet Grouting

The paper presents a numerical analysis to consider the effect of jet grouting in reducing the lateral displacement of the tunnels placed in the influential zone of deep excavation. A commercial software was adopted for the analysis. The hardening soil model is used to simulate the soil behavior. The diaphragm wall (D-wall) is first selected as the retaining wall structure. Due to the effect of the deep excavation on the available adjacent tunnel, jet grouting is added outside the deep excavation, in the middle of the tunnel and the deep excavation. The impact of jet grouting techniques is investigated by considering the relationship between the lateral displacement of the tunnel and parameters that control the characteristics of the jet grouting area. As a result, jet grouting can effectively reduce the influence zone of the deep excavation on adjacent tunnels and the tunnel lateral displacement to 32%. The results of the paper can serve as a practical guide to deep excavation.