摘要
根据"围岩-煤体"系统在开采过程中的运动变化特征,建立"一大两小"采场空间孕育模型,将顶板、煤层和底板作为一个完整的系统来考察煤岩结构破裂到失稳乃至冲击的过程,并以具有向斜构造和巷道交叉区域等典型孕育场的某矿区冲击煤层的微震现场实测研究予以论述。研究表明,空间孕育模型可以准确描述煤岩结构从破裂到失稳乃至冲击的整个过程,其中静态高应力集中区域是煤岩结构失稳破坏的应力基础,回采作业开启了强矿震和冲击的动态孕育过程,顶板断裂引发的动载荷可以触发动态孕育过程快速进入裂隙突变阶段乃至失稳破坏,强矿震和冲击的发生取决于走向上高应力集中区域能否在遭到逐渐卸载破坏前就已经达到较高的孕育程度。孕育过程中的裂隙稳定扩展阶段是强矿震和冲击前兆信息的异常阶段,裂隙突变说明强矿震和冲击的即将发生。该矿区1-3区二段工作面历次强矿震和冲击表现出明显的孕育特征,特别是"6·26","10·15"冲击前,矿震频次和能量异常活跃,孕育特征更为明显。
Based on variation characteristics of “surrounding rock-coal” system during coal mining, a space breeding model of stope was established in this paper. In the model, roof, coal seam and floor was regarded as a whole system to investigate the fracture, instability and burst process of coal-rock structure. In addition, this theory was verified through microseismic monitoring in a stope with strong rock burst tendentiousness.The results show that the space breeding model can accurately describe the entire process from stable state to instability of coal-rock structure. The area with high static stress con-centration is the stress basis for instability and failure of coal-rock structure. Mining operations launch the dynamic process of strong tremor and rock burst, and the dynamic load caused by roof fracture can quickly trigger the dynamic process into crack mutation stage and even lead to instability and failure of coal-rock structure. The emergence of strong tremor and rock burst depends on whether the high stress concentration area can reach high inoculation degree before it was unloaded and destroyed gradually. Crack extension stage shows the abnormal precursory information of strong tremor and rock burst, and the crack mutation stage predicts the occurrence of strong tremor and rock burst. The previous strong tremors and rock bursts in No.2 Workface of No.1-3 District show obvious breeding characteristics. Es-pecially before the rock bursts happened on 26th, Jun and 15th, Oct, the seismic events and energies are very active, which presents a more obvious breeding characteristics.
出处
《采矿与安全工程学报》
EI
北大核心
2014年第1期41-48,共8页
Journal of Mining & Safety Engineering
基金
高等学校博士学科点专项科研基金新教师类课题(20120095120019)
国家自然科学基金联合基金项目(51174285)
江苏高校优势学科建设工程项目(SZBF2011-6-B35)
煤炭资源与安全开采国家重点实验室自主研究课题项目(SKLCRSM12X08)
江苏省普通高校研究生科研创新计划项目(CXZZ12_0949)
关键词
采矿工程
冲击矿压
矿震
孕育模型
前兆信息
mining engineering
rock burst
tremor
breeding model
precursory information
