Under soft soil geological conditions, tunnel engineering disturbances can induce changes in ground surface surcharges and lead to stress redistribution in the surrounding soils. As relatively unfavorable loads during engineering disturbances, ground surface surcharges significantly influence both transverse and longitudinal deformations of shield tunnel structures, resulting in increased ellipticity, segment dislocations, joint openings, and tunnel settlement. This study investigates the effect of two different steel plate reinforcement methods—annular steel plates and cross-joint steel plates—on tunnel structures under surface surcharge loading. Using the Mohr–Coulomb elastoplastic constitutive model, the influence of surface surcharges on shield tunnel segment deformation and adjacent soil behavior is analyzed. Numerical modeling is performed based on surface loading parameters obtained from the river channel section of Metro Line 9 in an eastern region of China, and the model is validated through correlation between finite element analysis results and measured tunnel settlement data. The results indicate that annular steel plates exhibit effectiveness comparable to that of cross-joint steel plates in controlling tunnel ovalization and circumferential joint separation under surface surcharge conditions. However, cross-joint steel plates perform better in mitigating longitudinal deformations of the tunnel, including differential settlement and vertical displacement. In addition, cross-joint steel plates demonstrate a stronger capacity to control shear stress distribution within tunnel segments compared to annular configurations. These findings provide valuable references for shield tunnel engineering in load-disturbed environments.
Zhao et al. (Thu,) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: