Determination of three-level energy absorbing support parameters in rockburst roadway based on energy calculation
WANG Aiwen,FAN Dewei,PAN Yishan,DAI Lianpeng,XIAO Yonghui,XU Lianman,CHEN Jianqiang
辽宁工程技术大学 力学与工程学院辽宁工程技术大学 冲击地压研究院辽宁大学 物理学院东北大学 深部金属矿山安全开采教育部重点实验室神华新疆能源有限责任公司
煤矿冲击地压的工程治理主要集中体现在冲击地压启动前的“防”与冲击启动后的“止”,而如何依据冲击类型及能量特征设计吸能支护参数,有效地“止冲”对削弱冲击破坏程度具有重要意义。为实现冲击地压巷道吸能支护参数的量化设计,通过分析不同类型冲击地压释放的能量主体与破坏特征,指出了冲击危险巷道三级吸能支护方式的选择原则;基于能量守恒原理,考虑冲击释放能级、围岩破坏特征以及支护装备力学特性,给出了三级吸能支护参数的确定方法。研究结果表明:煤体压缩型冲击地压释能主体为煤体,释放能量一般不大于106 J;顶板断裂型冲击地压释能主体为顶底板围岩,坚硬顶板断裂时释放能量不低于106 J;断层错动型冲击地压释能主体为断层,释放能量在107 J以上。不同类型冲击地压发生后,巷道围岩表现出不同程度的震动破坏,吸能支护设计应遵循原则:冲击能量分级设防、锚杆锚索主动支护优先、全断面主-被动联合支护、巷道支护结构整体稳定性与经济性。进行防冲支护参数设计时应采用逐次递进法设计吸能锚索、吸能U/O型棚、吸能液压支架的支护参数,当吸能锚索支护间距小于0.8 m时,升级为二级吸能计算,当吸能U/O型棚的排距小于0.6 m时,升级为三级吸能计算。现场实践表明:基于能量法的巷道支护参数可靠,防冲效果显著。
The engineering treatment of rockburst in coal mines mainly reflects in the two aspects of“prevention”before the bursting start-up and "stop" after the rockburst initiation. Furtherly,involving the rockburst type and energy characteristics for parameters design of the energy absorbing support is important to effectively stop bursting and weaken the bursting damage degree. For quantitative design of energy absorbing support parameters in rockburst roadways,the main energy releasing bodies and failure characteristics of different type rockburst were analyzed and selection principles of three-level energy absorbing support in burst-prone roadway were proposed. Based on the energy conservation,the determination method of three-level energy absorbing support parameters was given,considering the energy level of rockburst release,the failure characteristics of surrounding rock and the mechanical characteristics of support equipment. The results show that,the main energy-releasing body of coal compression type rockburst is coal mass,and its released energy is not more than 106 J; the main energy-releasing body of roof fracture type rockburst is roof and floor,and its released energy is no less than 106 J; the main energy-releasing body of fault dislocation type rockburst is fault structure,and the released energy is more than 107 J. After the occurrence of different types of rock burst,the surrounding rock of roadway shows different degrees of vibration damage. Therefore,some principles should be followed in design of energy absorbing support,involving rockburst energy classification prevention,active support priority of bolt and cables,active-passive combined and overall-section support,overall stability of roadway support structure and economic applicability. Hierarchical progressive method should be used to quantitatively determine the burst-resistance support parameters,successively including the support parameters of energy absorbing anchor cable,U/O-shed and hydraulic support. When the support spacing of energy absorbing anchor cable is less than 0.8 m,design degree is upgraded to two-level energy absorbing calculation; when the row spacing of energy absorbing U/O-shed is less than 0.6 m,corresponding degree is upgraded to three-level. The field practice shows that the parameter design method of three-level energy absorbing support based is reliable and the effect of burst-resistance of roadway is remarkable.
rockburst; rockburst types; energy-releasing body; three-level energy absorption support; energy calculation
0 引言
1 巷道冲击地压类型及能量估算与破坏特征
1.1 煤体压缩型冲击地压能量与破坏特征
1.2 顶板断裂型冲击地压能量与破坏特征
1.3 断层错动型冲击地压能量与破坏特征
2 基于巷道围岩结构特征的支护方式选择
2.1 冲击地压巷道梯度结构特征
2.2 吸能支护方式选择原则
3 防冲吸能支护装备及力学特性
4 冲击地压巷道三级吸能支护参数的能量计算方法
4.1 三级吸能支护分级支护特点
4.2 三级吸能支护设计主要流程
5 应用算例
5.1 工程概况
5.2 计算过程
5.3 应用效率
6 结论
主办单位:煤炭科学研究总院有限公司 中国煤炭学会学术期刊工作委员会