深井动压巷道围岩弱化规律及高强锚固群围岩控制机理研究

The sourrounding rock of deep roadway is comprehensive influenced by the unfavorable factors of high stress,high ground temperature and high karst hydraulic etc, the sourrounding rock of roadway is very difficult to be controlled,it has become the key factor to restrict safety and high effective product of deep mining.The project will take the mining areas of Hunan Zhouyuanshan,Guizhou Panjiang, Hebei Kainan etc for engineering background,the following contents are mainly researched in this project:(1) Under the high stress of deep mining,high ground temperature and dynamic pressure the cracked body of roadway sourrounding rock generation→extension→transfixion→failure whole process space time evolution regularity and weaken degree;(2)The space time evolution relationship between the high stress of deep mining, high ground temperature gradient and magnitude of dynamic pressure and the strength of anchoring body;(3)The maximum anchorage radius of the single high strength bolt and the internal &external mechanical conditions of the several bolts are formed high strength group of archorage bodies by archoring;(4) The stable conditions and criterions of combination blocks which are formed by the high strength group of archorage bodies. Throuth research of this project, it will reveal the weaken regularity of the deep roadway surrounding rock and the mechanism of sourrounding rock controlling of high strength group of archorage bodies, recognize migration rules of the dynamic pressure roadway sourrounding rock and distribution state of the plastic zone under the conditions of nonlinear mechanical mechanism in the deep mining, put forward the new support principle and new technology for deep roadway under dynamic pressure,it is very impromant for further enrich and develop the theory and technology of roadway sourrounding rock controlling.

深部巷道围岩在高应力、高地温及高岩溶水压等不利因素综合影响下，巷道围岩控制极为困难，成为制约深部矿井安全高效生产的瓶颈。本项目以湖南周源山、贵州盘江、河北开滦等矿区深部动压巷道为工程背景，重点研究以下内容：（1）深井高应力、高地温及开挖回采动压作用下巷道围岩体裂隙产生→扩展→贯通→破坏全过程的时空演化规律及弱化程度；（2）深井高应力、高地温梯度及动压大小与围岩强度弱化的时空演化关系；（3）单根锚杆的最大锚固半径及多根锚杆锚固形成高强度锚固群的内、外部力学条件；（4）高强锚固群形成组合块体的稳定条件及判据。通过本项目研究，将揭示深部巷道围岩的弱化规律及高强锚固群控制围岩机理，认识深部非线性力学机制条件下动压巷道围岩运移规律及塑性区分布状况，提出深井动压巷道支护新原理与新技术，对于进一步丰富和发展巷道围岩控制理论和技术具有重要意义。

在未来相当长的时间内，煤炭资源仍是我国能源的主体，而我国深部煤炭资源占比超过50%，随着浅部煤炭资源的枯竭，深部开采是必然之势。深部复杂的物化环境使得深部岩体表现出特有的变形破坏特征，尤其是深井动压巷道围岩极难得到有效的控制。因此，本项目基于深井动压巷道实际情况，综合运用现场调研、实验室试验、理论分析和数值计算等手段，针对深井动压巷道围岩弱化规律及高强锚固群围岩控制机理进行研究。研究的主要内容包括：高应力高地温下巷道围岩弱化规律、深井动压巷道矿压显现规律以及深部巷道围岩高强锚固群控制机理等三个方面。.深井动压巷道围岩表现出大范围塑性变形和具有强流变变形特性，在扰动作用下往往出现快速大变形破坏。针对高应力软岩近距离巷道工程的掘进扰动推导了掘进爆破扰动波在岩体中的衰减方程。深井动压巷道围岩处于高频变化的高应力状态之下，强度弱化非常明显。提出了基于能量密度的损伤指标和考虑应力状态过程的围岩强度弱化计算方法。研究了巷道围岩塑性区的演化规律及其影响因素。深井动压巷道围岩多为裂隙岩体，采用锚固裂隙类岩材料研究锚杆对该类岩体的锚固作用机理，并提出了主控裂纹的概念。锚杆能够有效遏制主控裂纹的快速发展，显著提高裂隙岩体的残余强度。建立了三种锚杆力学模型，结合岩体破坏准则求解了全长锚固锚杆的有效锚固半径。研究了单根高强度锚杆在不同锚固条件下形成的高强度锚固体纵、横向有效锚固半径及其改变和提高有效锚固范围内巷道围岩体力学参数的性能；探讨了顶板纵向上锚固范围内会形成系列的锚固串群体的组合形式及稳定条件和判据。研制了新型可延伸锚杆，根据不同条件提出了多种深井动压巷道围岩控制技术并进行了现场应用与推广。对于进一步丰富和发展深部巷道围岩控制理论和技术具有重要的现实意义。