摘要
针对木城涧煤矿大台井在-510 m水平掘进过程中所揭露出的两类不同性状的玄武岩,采用实验室内试验和现场测试相结合的方法,从岩石力学性质、细观结构、地应力等方面分析了井下产生岩爆的地质力学机理。宏观力学性能测试表明,具有岩爆性的B类玄武岩强度大、抗变形能力强,峰前容易积聚大量的变形能,峰后能量释放更为迅速强烈;B类试件在单轴压缩过程中,从30%极限强度开始便出现声响,最终试件破坏崩解成碎块。SEM扫描显示,与A类玄武岩相比,B类岩石结构排列整齐致密,不存在裂隙;B类岩样中的硅、氧含量明显偏高,地质硅化作用明显。井下现场地应力测试表明,该区域的最大主应力为近水平方向,实测值达到45.69 MPa,方位基本与巷道北帮垂直。大台井B类玄武岩的特殊细观结构和元素组分决定了其宏观岩爆倾向性,岩石本身的物理力学性质是岩爆发生的内因;地应力是岩爆发生的主要力源条件,其控制着岩爆发生的区域和能量大小。
Based on the two kinds of different characters of basalt revealed in-510 m level of Datai Mine,the geomechanical mechanism of rock burst in mine was analysed from the aspects of mechanical quality,microscopic structure and in-situ stress by testing in laboratory and field testing.Macroscopic mechanical properties test shows that the strength of B-class basalt which is prone to burst is bigger and its accumulating deformation ability is stronger.The deformation energy is accumulated easily before the peak of stress and can be released more quickly after the peak.In the uniaxial compression test of B-class basalt,noise began to appear from the moment that the stress reach 30% of its ultimate strength and the specimens was breaked to fragments finally.SEM scanning shows that compared with the A-class basalt,the structure is compact and few fissures exist in B-class basalt,the content of silicon and oxygen is on the high side and the effect of geological silicification is significant of B-class basalt.Underground in-situ stress tests show that the direction of maximum principal stress is horizontal nearly,perpendicular to the north working slope of tunnel and its magnitude reaches 45.69 MPa.The special microstructure,element compositions of B-class basalt determines its burst tendency.The physical and mechanical properties is the internal reason of rock burst while the in-situ stress is the main force and it determines the range,energy size of rock burst.
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2010年第12期2039-2044,共6页
Journal of China Coal Society
基金
国家重点基础研究发展计划(973)资助项目(2010CB226805)
国家自然科学基金资助项目(51074099
51004068)
山东省高等学校优秀青年教师国内访问学者资助项目
山东科技大学"矿山压力与岩层控制"创新团队基金资助项目
关键词
岩爆
力学机理
细观结构
地应力
深部开采
rock burst
mechanical mechanism
microscopic structure
in-situ stress
deep mining
