基于煤矿井下综合应力场的煤岩动力灾害预测与控制基础研究

With the increase of the mining rate and depth, roof-caving accidents, mine bumps and other dynamic disasters pose a great threat to the safety and high efficient production of China’s coalmines. The mining-induced stresses are the instrinsic reasons to cause dynamic disasters. Based on the integrated stress field composed of in-situ stresses, mining induced stresses and support stresses, and the interaction of the above three stress fields, this project will apply following researching approaches, i.e. theoretical analysis, laboratory testes, numerical simulations and underground field testes. This project will also create the large scale mechanical model of jointed coal and rock massed under the condition of different mining dynamic loads to study the coupling effects among the integrated stress field, the strengths of coal and rock masses and geological structures. The project will study the evolution process of the integrated stress fields in the in situ rock masses, mining-disturbed rock masses and supported rock masses, joint mapping characteristics and the energy field, which will form a base to account for the mechanisms of dynamic disasters of coal and rock masses. Based on the evolution process of the integrated stress field and joint mapping characteristics, roof separation jump, overburden displacement characteristics, the damage characteristics of coal and rock masses, a decision-making model system for the prediction and control of dynamic disasters of coal and rock masses will be formed to provide the general method for information monitoring and disaster control. This project will select some typical mines, where geomechanical testes will be carried out, and mining-induced stresses, support stresses, the roof separation, the deformation and the damage of coal and rock masses will be monitored. The prediction and control of dynamic disasters will be carried out, and the correctness of research results will be verified by the underground testes.

随着煤矿开采强度与深度的不断增加，顶板垮落、冲击地压等煤岩动力灾害严重影响我国煤矿的安全、高效生产，而动力灾害发生的根本驱动力是采动煤岩应力。本项目以煤矿井下综合应力场，即由原岩应力、采动应力及支护应力形成的应力场及其相互作用为主线，采用理论分析、实验室试验、数值模拟、井下试验相结合的方法开展研究。建立不同采动条件下煤岩体大尺度节理裂隙结构力学模型，研究综合应力场与煤岩体强度、结构的耦合关系；研究不同采动条件下综合应力场、裂隙场、能量场演化过程，以此为基础揭示煤岩动力灾害的成灾机理；基于综合应力场与裂隙场演化、顶板离层突变、覆岩运动及破坏特征建立煤岩动力灾害预测和控制决策模型体系，形成灾害综合信息监测与控制方法。选择典型矿井，开展地质力学测试与采动应力、支护应力、顶板离层、煤岩变形及破坏的现场监测，进行煤岩动力灾害的预测与控制，通过井下试验，验证理论研究成果的正确性。

本项目针对煤矿顶板垮落、冲击地压煤岩动力灾害，以应力变化及控制为主线，围绕综合应力场演化、大尺度节理裂隙模型建立、煤岩动力灾害预测及控制开展研究，取得了一些新进展。在煤矿井下综合应力场演化方面，提出了综合应力场概念与内涵；发现了原岩应力场分布规律，建立了描述地质力学参数之间关系的公式；开发了三维采动应力实时监测系统，并以潞安矿区为例揭示了采动应力演化规律；实验室试验揭示出锚杆支护应力场在围岩中的分布特征；数值模拟揭示出原岩、采动、支护三种应力场相互关系。在煤岩体大尺度节理裂隙模型建立分析方面，建立了大尺度煤体离散裂隙网格模型，揭示了原生裂隙对煤体破坏影响规律；采用CT扫描、节理裂隙三维重构结合数值计算，揭示了不同加载及支护下煤岩体受力变形破坏特征及裂隙场演化规律。基于前述综合应力场演化规律及节理裂隙对煤岩体受力、变形破坏的影响，针对顶板垮落，提出了顶板离层界限值的概念及顶板离层预警判据；针对冲击地压，基于应力场演化，参考地震预测方法并结合煤矿采动影响特点，提出了冲击地压预测方法。在煤岩动力灾害控制方面，提出冲击地压巷道支护方法；发明了强烈动压巷道水力压裂卸压方法；建立了冲击地压灾害预警决策模型和基于冲击启动理论的采掘空间冲击地压控制方法，并结合现场工程问题开展了具体的应用研究，为井下煤岩动力灾害防治提供了参考。四年来，发表学术论文47篇，其中SCI收录5篇，EI收录20篇；出版专著1部；获国家科技进步一等奖1项，省部级科技奖励9项；申请发明专利9项(8项获授权)，实用新型专利20项(已获授权)。项目负责人康红普当选中国工程院院士，入选国家“万人计划”百千万工程领军人才；项目培养青年科技人才4名，培养博士研究生6名，硕士研究生7名；项目组成员参加国际学术交流10余次，参加国内学术交流会议30余次，并多次作特邀报告。