摘要
研究目的:施工引起的扰动地应力对两单并行的深埋隧道硬质岩岩爆风险具有重要影响,并可能造成先行洞发生时滞型岩爆风险。然而,目前对隧道施工扰动应力区分布特征和工程影响研究不足,难以满足秦岭地区两单并行铁路隧道线间距精细化设计的要求。本文通过施工期洞内实测地应力数据综合分析和对比,从而确定秦岭地区自然岩体扰动应力的主要分布规律和工程影响。研究结论:(1)按照扰动应力-深度曲线特征划分,硬质岩体可以分为两种端元模式,即近均质体、微结构面岩体模型和相对均质、主结构面控制岩体模型;(2)隧洞内实测地应力结果显示,秦岭地区硬质岩大部分接近于主结构面控制模型,其扰动应力区影响范围为18~25 m;少量近均质体微结构面模型,其影响深度为7~10 m;(3)Ⅱ、Ⅲ级硬质围岩扰动应力区范围可分别按照10 m、25 m考虑,建议两并行单线铁路隧道线间距在此基础上预留一定的安全值进行设计;(4)本研究成果可推广应用于秦岭及类似山区铁路、公路地质选线以及隧道岩爆风险防控方面。
Research purposes:Disturbed in-situ stress caused by construction has an important impact on the risk of rock burst in parallel deep-buried tunnels,and may lead to delayed rock burst in the preceding tunnel.However,the existing research is difficult to meet the needs of assessing the scope of the disturbed in-situ stress zone during railway tunnel construction,which in turn makes it difficult to satisfy the requirements for the refined design of the clear distance between two parallel single-track railway tunnels.Based on the comprehensive analysis and comparison of measured in-situ stress data in tunnels,the main law and depth range of the disturbed in-situ stress in the Qinling natural rock mass are determined.Research conclusions:(1)According to the characteristics of the disturbed in-situ stress-depth curve,natural hard rock mass can be divided into two end-element models,namely,the homogeneous rock mass model without structural plane and the relatively homogeneous rock mass model with structural plane.(2)The measured in-situ stress of hard rock in Qinling area is mostly close to the model with structural plane,and the depth of disturbed in-situ stress zone is 18~25 m;a few cases can be considered as the mode without structural plane,with a depth of 7~10 m(.3)The disturbed in-situ stress zone of Class II and III surrounding rock can be considered as 10 m and 25 m,respectively.Therefore,it suggests that the clear distance between two parallel single-track high-grade railway tunnels should reserve a sufficient safety value according to this rule.(4)This achievement can be applied to the geological route selection of railways and highway in Qinling and similar mountainous areas and to the prevention and control of rock burst risk in tunnels.
作者
陈兴强
黄勇
李玉波
罗锋
常帅鹏
何志杰
高斌
董凡
CHEN Xingqiang;HUANG Yong;LI Yubo;LUO Feng;CHANG Shuaipeng;HE Zhijie;GAO Bin;DONG Fan(National Key Laboratory of Intelligent Construction and Maintenance of Geotechnical and Tunnel Engineering in Extreme Environments,Xi'an,Shaanxi 710043,China;China Railway First Survey and Design Institute Group Co.,Ltd.,Xi'an,Shaanxi 710043,China)
出处
《铁道工程学报》
北大核心
2025年第10期16-21,共6页
Journal of Railway Engineering Society
基金
国家自然科学基金(42102266,42202240)
西藏自治区重点研发计划项目(XZ202501ZY0108)
中国铁建重大专项(2023-Z03,2024W02)
陕西省科技厅科技计划项目(2023-YBSF-238)。
关键词
扰动地应力
隧道
岩爆
线间距
disturbance stress
tunnel
rock burst
railway route selection
