Study on Risk Assessment and Control Countermeasures of Surrounding Rock Deformation of Xiangshan Tunnel
This paper aims to solve the problems induced by fractured rock mass in tunnels,such as complicated stress conditions,poor stability,deformation proneness,and the risk of destabilization.Based on the excavation of the entrance section of Xiangshan Tunnel,this paper explored the relationship between tunnel excavation and surrounding rock deformation through theoretical analysis;the tunnel deformation was calculated using FLAC3D software and the risk of surrounding rock deformation during excavation was evaluated;A comparative analysis was performed on the deformation range of surrounding rocks under different excavation methods,thereby selecting the optimal excavation method;The deformation condition of surrounding rocks was referenced to present a combined support scheme with a numerical calculation model constructed to verify it.The research results showed that with no support applied,the maximum subsidence of the vault is 663 mm,and the maximum floor heave is 451 mm,causing the risk of deformation and destabilization;The comparison of different excavation methods implied that compared with the full-section excavation,the double-bench method and the three-bench method reduce the vault settlement by 2%and 5%,respectively,and the use of the bench method excavation allows the early application of support,and thus the stability of surrounding rocks is enhanced;Under the joint support of"shotcrete + anchor bolt + steel arch",the maximum vault settlement is 36.6 mm,within the normal settlement range,indicating that this scheme can effectively control the tunnel deformation.
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万方数据
维普
