摘要
深部岩体工程围岩蠕变性强,受外部中量级循环冲击载荷(冲击能量等级介于10^(3)~10^(5) J)扰动影响时会发生长期大变形动力灾害。基于近年来对岩石蠕变扰动效应理论的相关研究,采用岩石动力学试验、围岩动态变形破坏理论分析并结合现场工程实践的综合研究方法,对中量级冲击载荷作用下深地岩体工程的长期大变形机制以及稳定性控制进行了系统研究。通过研究,总结分析了岩石蠕变扰动变形规律,确定了蠕变岩石对外部冲击扰动敏感的应力、应变阈值指标;根据地应力梯度与围岩强度梯度关系重新划分了深地动压工程围岩状态区域,发现了以围岩蠕变扰动敏感区动态演化发育为本质的深地围岩长期大变形失稳机制新认识;探讨了围岩应力场分布及演变规律,确定了深地动压岩体工程长期稳定性控制原理,即给扰动敏感区边界处提供足够的侧向围压,使该区域围岩的抗扰动强度梯度提高至静载集中应力水平,迫使扰动敏感区消失;基于理论分析、实验室测试以及现场动载监测等手段,提出了深地动压岩体工程围岩支护设计方法,优化了支护参数设计流程,并在多个工程实例中取得了良好的应用效果。
The surrounding rock of deep engineering shows obvious creep characteristics.When it is affected by the external cyclic impact load with medium-grade energy(impacting energy of 10^(3)~10^(5) J),a long-term large deformation dynamic disaster will occur.Based on the recent researches on the theory of creep disturbance effect of rock,the long-term large deformation mechanism and the stability control of deep dynamic engineering under cyclic medium-grade impact load are studied.The comprehensive research methods include the rock dynamics experiment,theoretical analysis of dynamic deformation and failure of the surrounding rock combined with the field engineering practice are adopted.According to the researches,the deformation law of creep disturbance of rock is summarized and analyzed.The stress and strain threshold indexes of creep rock mass sensitive to the external impact disturbance are determined.According to the relationship between the in-situ stress gradient and the strength gradient of surrounding rock,the state zone of the surrounding rock in deep dynamic engineering is re-divided.A new understanding about the mechanism of long-term large deformation and instability in deep surrounding rock is discovered based on the dynamic movement of e sensitive zone of disturbanc within the surrounding rock.The distribution and evolution law of the stress field in the urrounding rock is discussed.Then the long-term stability control principle of deep dynamic engineering is determined.That is,the supporting structures provide sufficient lateral confining pressure at the boundary of the sensitive zone of the disturbance.The lateral confining pressure must increase the anti-disturbance strength gradient in this zone to the static concentrated stress level.It can make the sensitive zone of disturbance disappear.The design method for support of the surrounding rock for deep dynamic engineering is also proposed based on the theoretical analysis,laboratory testing and field monitoring of dynamic load.The designing process of supporting parameters is optimized.The research findings have been applied in multiple field engineering examples with ideal results.
作者
黄万朋
孙远翔
陈绍杰
HUANG Wan-peng;SUN Yuan-xiang;CHEN Shao-jie(College of Energy and Mining Engineering,Shandong University of Science and Technology,Qingdao 266590,China)
出处
《岩土工程学报》
EI
CAS
CSCD
北大核心
2021年第9期1621-1630,共10页
Chinese Journal of Geotechnical Engineering
基金
国家自然科学基金项目(51774195,51304127)
山东科技大学科研创新团队支持计划项目(2019TDJH101)。
关键词
深地工程
蠕变扰动
动力灾变
机制分析
支护控制
deep engineering
creep disturbance
dynamic disaster
mechanism analysis
supporting system
