Stability Analysis and Safety Evaluation of Surrounding Rock in Shallow-buried Concealed Tunnel Construction
Abstract
In the construction of shallow-buried concealed tunnels, the control of surrounding rock stability is a core challenge, which is crucial to construction safety and structural performance. A two-dimensional model was established using Midas GTS NX, combined with bench cut method excavation simulation. The laws of vault and surface settlement were quantitatively analyzed through displacement nephograms, and the spatiotemporal characteristics of surrounding rock displacement were revealed. The results show that under the established excavation and support measures, the displacement and settlement meet the specification requirements. Meanwhile, the Analytic Hierarchy Process (AHP) was introduced to determine weights and analyze the coupling correlation of factors through judgment matrices, clarifying the influence degrees of surrounding rock grade, support strength, and other factors to achieve multi-dimensional evaluation. Furthermore, the Fuzzy Comprehensive Evaluation method was integrated to quantify the mapping relationship between surrounding rock stability and safety, and the safety grade was obtained. Finally, measures such as strengthening support, optimizing excavation parameters, refined exploration, and improving management were proposed to enhance surrounding rock stability and reduce construction risks.
References
Peck R, 1969, Deep Excavations and Tunnelling in Soft Ground. Proceedings of the 7th International Conference on Soil Mechanics and Foundation Engineering. New York: IEEE, 225–290.
O’Reilly M, New B, 1982, Settlement Above Tunnels in the UK: Their Magnitude and Prediction: 172–182.
Dindarloo S, Siami-Irdemoosa E, 2015, Maximum Surface Settlement-Based Classification of Shallow Tunnels in Soft Ground. Tunnelling and Underground Space Technology Incorporating Trenchless Technology Research, 49: 320–327.
She F, Wang Y, Zhang Y, 2015, Laws and Prediction Analysis Methods of Longitudinal Surface Settlement Induced by Underground Excavation of Metro Tunnels in Loess Strata. Rock and Soil Mechanics, 36(S1): 287–292.
Wang X, Tan W, Ni P, et al., 2020, Propagation of Settlement in Soft Soils Induced by Tunneling. Tunnelling and Underground Space Technology Incorporating Trenchless Technology Research, 99: 103378.
Lu D, Kong F, Du X, et al., 2019, A Unified Displacement Function to Analytically Predict Ground Deformation of Shallow Tunnel. Tunnelling and Underground Space Technology Incorporating Trenchless Technology Research, 88: 129–143.
Cao S, 2022, Study on Failure Modes and Laws of Surrounding Rock in Shallow-Buried and Biased Tunnels. Railway Standard Design, 66(04): 143–148.
Dai J, Yang K, Shang X, et al., 2022, Calculation of Loose Surrounding Rock Pressure for Shallow-Buried Underground Excavation Tunnels in Loess Strata. Journal of Safety Science and Technology, 18(7): 142–148.
Guan H, Zhu Y, 2023, Numerical Simulation of Surface Settlement Variation Law Induced by Double-Line Tunnel Shield Propulsion. Journal of Guangdong University of Petrochemical Technology, 33(01): 57–61.
Wang J, 2022, Stochastic Finite Element Numerical Simulation Analysis of the Impact of Shield Tunnel Undercrossing on Airport Runways. Construction Technology (Chinese & English), 51(21): 23–29.
Zhu B, 2023, Numerical Simulation Analysis of Mutual Superposition Influence in Overlapping Shield Tunnel Construction Based on MIDAS. Anhui Architecture, 30(04): 139–141.
Yang H, Li J, Chen Z, et al., 2008, Laws of Longitudinal Surface Subsidence During Construction of Shallow-Buried Underground Excavation Tunnels. Journal of Nanjing Tech University (Natural Science Edition), 2008(03): 56–60.
Cheng Z, Dai Y, Yuan M, et al., 2021, Research on CRD Method Construction Technology for Large-Section Continuous Variable-Section Rectangular Tunnels with Shallow-Buried Underground Excavation[J]. Sichuan Building Materials, 47(04): 97–98.
Miao X, Fan S, Mi W, et al., 2020, Analysis on Surrounding Rock Deformation Characteristics During Construction of Shallow-Buried Underground Excavation Tunnels in Gentle Slope Sections of Loess Tableland Areas. Railway Engineering, 60(07): 51–54.
Teng H, 2022, Stability Analysis and Risk Evaluation of Surrounding Rock for Double-Shield TBM Crossing Fault Fracture Zones in Qingdao Metro, thesis, Qingdao University of Technology.
