摘要

The construction of a shallow-buried tunnel inevitably disturbs the stratum and causes ground settlement, especially in the building zone, where all ground loads act on building foundations, readily causing tunnel structure deformation and building settlement. Therefore the optimization of construction schemes is vital for controlling excessive deformations of the surrounding rock and reducing the settlements of surface buildings. Based on the construction of the Renhechang tunnel on the Lanzhou-Chongqing railway underneath surface buildings, a numerical simulation was carried out regarding the bench cut method, CD method, and CRD method, and a contrastive analysis of the displacement field of surrounding rock and the distribution characteristics of the plastic zone was conducted. Additionally a study of the disturbance effect of excavation on surrounding rocks near the working face was performed, and the space-time effect of surrounding rock deformation and the influence on foundation settlement were analyzed. The soundest and most economic construction scheme is presented. The results show that bench cut method is feasible for the Renhechang tunnel construction.

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