摘要
针对深埋硬岩隧洞围岩脆性破坏分析时传统应力指标的局限性和相应防治措施理论研究不足的特点,在数值分析中应用反映高地应力下硬岩脆性破坏特点的RDM本构模型,结合局部能量释放率评价指标分析硬岩脆性破坏过程中能量释放的强弱,对深埋隧洞开挖过程中防治围岩脆性破坏的设计及施工措施进行综合性研究。首先,通过评价隧洞群洞间距、施工进度等设计方案对围岩能量释放的影响,提出预防岩爆发生的区域性对策。然后,针对能量释放的时空演化规律,本着减压卸能的原则,给出支护时机、支护类型和参数的设计建议。同时,在施工控制措施方面通过分析在掌子面上布置应力释放孔爆破卸压防治岩爆的效果,给出应力释放孔布置方案的优化建议。最后,应用上述方法对锦屏二级水电站辅助洞围岩的脆性破坏提出工程防治措施,实践结果表明,所提出的防治对策完全可行,可供类似工程借鉴。
Aiming at the insufficient theoretical study on rockburst prevention and the limited evaluation of traditional stress index in the tunneling in deep hard rock, a new method for rockburst prevention measures based on local energy release rate index is proposed. The design and construction control measures in the process of tunneling is comprehensively researched by using energy release rate index, which is analyzed in the numerical calculation using a new constitutive model reflecting the brittle failure of hard rock. First tunnel pitch and different tunneling sequences are proposed as a regional prevention measure by comparing the energy release magnitude of rock wall. Then the support opportunity and parameters of the design proposal are given based on the destress principle in the space-time evolution of the energy release. Meanwhile, the effect of the stress release hole for rockburst prevention is analyzed in the process of construction, the layout pattern of stress release hole is also optimized. At last, the prevention measures of rockburst failure for Jinping II Hydropower Station diversion tunnels are proposed. The practical results show that the proposed control measures are entirely feasible; and the method could benefit other similar projects.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2008年第10期2064-2071,共8页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学基金重点项目(50539090)
国家自然科学基金青年基金资助项目(50709037)
国家科技支撑计划项目(2006BAB04A06)
中国科学院知识创新工程重要方向项目(KZCX2–YW–109–3)
关键词
隧道工程
深埋隧洞
岩爆
防治措施
局部能量释放率
应力释放孔
tunnelling engineering
deep tunnel： rockburst： prevention measures
local energy release rate
stressrelease hole
