摘要
锁脚锚杆在软弱围岩隧道中应用非常广泛,为研究其受力特性,以天津关软岩隧道为依托,采用现场试验与理论分析相结合的方法,研究锁脚锚杆的支护效果、提出进一步优化措施,并研究锚杆直径和长度对支护效果的影响。研究结果表明,虽然ϕ42×4锁脚锚杆的支护效果好于ϕ22早强砂浆锁脚锚杆,但依然不能很好地控制围岩变形。相比ϕ42×4锁脚锚杆,ϕ89×6锁脚锚杆能很好地控制围岩变形,说明锁脚锚杆管径对其支护效果具有重要影响。围岩变形速率与隧道开挖过程有密切关系,采用三台阶七步开挖法施工时,要特别重视第3步开挖时的支护。
The feet⁃lock bolt is widely used in soft surrounding rock tunnels.To study its mechanical properties,based on the Tianjinguan soft rock tunnel,this paper,in combination with field test with theoretical analysis,studies the support effect and optimization of the feet⁃lock bolt and the influence of its diameter and length on support effect.The results show that,although the support effect of a ϕ42×4 feet⁃lock bolt is better than that of a ϕ22 early strength mortar one,the former doesn’t control the deformation of surrounding rock well.Compared with the ϕ42×4 feet⁃lock bolt,the ϕ89×6 plays a good role in controlling the deformation of surrounding rock,which indicates that the diameter of a feet⁃lock bolt has an important influence on the support effect.The deformation rate of surrounding rock is closely related to the process of tunnel excavation,and in the construction of a three⁃bench seven⁃step excavation method,special attention should be paid to the support of the third step excavation.
作者
佟晓冬
郭金冀
谭贤君
TONG Xiaodong;GUO Jinji;TAN Xianjun(No.5 Engineering Co.,Ltd.of CCCC First Highway Engineering Co.,Ltd.,Beijing100024,China;State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan,Hubei430071,China)
出处
《施工技术（中英文）》
CAS
2022年第13期81-83,90,共4页
Construction Technology
基金
国家自然科学基金优秀青年基金项目(51922104)。
关键词
隧道
软弱围岩
锁脚锚杆
支护
变形
tunnels
soft rock
feet⁃lock bolt
supports
deformation
