摘要
针对极高地应力环境深埋铁路TBM隧道施工中面临的时滞性岩爆与隧底隆起难题,聚焦揭示高地应力环境下围岩动力响应机制并优化工程防控体系,以保障TBM安全施工。研究采用现场岩爆地质力学分析、数值模拟与工程实践验证相结合的方法,系统分析高地应力场、围岩力学特性、地形地貌及施工扰动影响,利用微震监测手段捕捉围岩破裂演化,通过数值模拟验证支护措施的可靠性。研究结果揭示了极高地应力深埋硬岩隧道时滞性岩爆特征,其时空滞后效应源于硬岩内部能量积累达到临界阈值后与开挖卸荷应力扰动的耦合作用,且受控于岩石固有属性、地应力状态、地形地貌及施工扰动等多重因素;识别并提出微震监测事件数、能量密度等参数可作为预警时滞性岩爆潜在发生区域和位置的关键前兆信息;基于灾变特征,创新性构建“主动防控-分级处治-动态调控”三位一体的综合防控体系。研究结论表明:(1)提出的时滞性岩爆微震预警方法结合地质信息可有效识别高风险区域;(2)数值模拟与工程实践验证证实,在极高地应力作用下,现有支护体系可控制围岩变形在4 cm以下;(3)针对时滞性岩爆导致的隧底隆起,制定了三级渐进式处治方案,可提升工效40%以上,且结构稳定性满足施工期动态荷载及运营期长期承载要求。
In the construction of deep-buried railway tunnels by tunnel boring machines(TBM)under extremely high in-situ stress,the challenges of time-delayed rockbursts and tunnel floor heave need to be addressed.This study focuses on revealing the dynamic response mechanisms of surrounding rock under high in-situ stress and optimizing the engineering risk prevention and control system to ensure safe TBM tunneling.A combined approach of field geomechanical analysis of rockbursts,numerical simulation,and engineering practice verification was adopted.It systematically analyzed the influences of high in-situ stress fields,the mechanical properties of surrounding rock,topography,and construction disturbance.Microseismic monitoring was used to capture the fracture evolution of the surrounding rock,and numerical simulations were applied to verify the reliability of support measures.The research results revealed the characteristics of time-delayed rockbursts in deep-buried hard rock tunnels under extremely high in-situ stress.This spatiotemporal delay was due to the coupling effect between the energy accumulation within hard rock reaching a critical threshold and the excavation unloading stress disturbances.This process was controlled by multiple factors,including rock properties,in-situ stress state,topography,and construction disturbance.The study identified parameters such as microseismic event counts and energy density as key precursors for predicting the potential occurrence areas and locations of time-delayed rockbursts.Based on the disaster characteristics,an innovative three-in-one comprehensive prevention and control system was proposed,integrating proactive prevention,graded treatment,and dynamic regulation.The research concluded that:(1)The proposed microseismic early-warning method,combined with geological information,effectively identified high-risk areas.(2)Numerical simulations and engineering practice verification confirmed that the existing support system could control surrounding rock deformation to below 4 cm under extremely high in-situ stress.(3)To address tunnel floor heave caused by time-delayed rockbursts,a three-level progressive treatment scheme was developed,which improved construction efficiency by more than 40%while ensuring structural stability under both dynamic loads during construction and long-term operational loads.
作者
丁彦杰
靳宝成
向亮
周泽华
常帅鹏
DING Yanjie;JIN Baocheng;XIANG Liang;ZHOU Zehua;CHANG Shuaipeng(State Key Laboratory of Intelligent Geotechnics and Tunnelling,Xi'an 710043,China;China Railway First Survey and Design Institute Group Co.,Ltd.,Xi'an 710043,China)
出处
《铁道标准设计》
北大核心
2025年第10期201-208,230,共9页
Railway Standard Design
基金
国家重点研发计划项目(2022YFB2302402)
陕西省创新能力支撑计划项目(2024ZC-KJXX-130)
中国铁建股份有限公司地下空间领域资助项目(2024-W24)。
关键词
铁路隧道
防控对策
灾变特征
极高地应力
时滞性岩爆
微震监测
railway tunnels
prevention and control countermeasures
disaster characteristics
extremely high in-situ stress
time-delayed rockburst
microseismic monitoring
