复杂条件下煤岩体耦合致裂基础研究

项目名称： 复杂条件下煤岩体耦合致裂基础研究

项目编号： No.51504184

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 矿业工程

项目作者： 崔峰

作者单位： 西安科技大学

项目金额： 20万元

中文摘要： 复杂条件下特厚煤层高效致裂与煤岩体动力灾害的卸压防治是综放开采的基础。为此聚焦于煤岩体安全高效致裂，提出耦合致裂：在煤岩体已被注水弱化的基础上实施爆破。从煤岩表面变形和内部破坏两方面追踪耦合致裂过程中裂纹发育特征，分析水/气传导、演化规律与裂纹发育间的因果联系，在微观层面上揭示煤岩体耦合致裂机制，给出耦合致裂时裂纹的扩展准则。运用非线性动力分析LS-DYNA程序计算获得爆炸荷载并施加于注水后的模型，研究耦合状态下煤岩体的动力响应特征，探索耦合致裂后模型的承载能力演化特性。针对耦合致裂效果定量化评估，构建等效于煤岩体耦合致裂后强度的力学模型。通过完成煤岩体整体–散体的等效离散化转化，揭示耦合致裂后顶煤的垮放流动规律、离散态颗粒间的铰接关系及其对垮放程度的影响，量化装药量、注水压力和煤体垮放能力之间的映射关系，形成复杂条件下煤岩体耦合致裂技术，实现复杂条件下煤岩体耦合致裂效果的定量化评估。

中文关键词： 岩层控制；动力灾害；多场耦合；急倾斜；数值模拟

英文摘要： Extra-thick coal seam high-efficient fracturing and coal-rock dynamic disasters relief control under the complex conditions are the basis of fully mechanized top coal caving mining. Focus on safety and high efficiency coal-rock fracturing, the coupled-crack is proposed: blasting is done on the weaken coal-rock mass by water injection. From the surface deformation of coal-rock and internal damage, the crack development characteristics are tracked during the process of coupled-crack. The causal link of water/gas conduction and evolution with the crack development is analysed to reveale the coal-rock coupled-crack mechanism at the micro level and give the crack extension criterion induced by coupled-crack. Using the nonlinear dynamic analysis program LS-DYNA, explosive load is obtained and applied to the water injection model so that the dynamic response characteristics of coal-rock is studied to explore the bearing capacity evolution characteristics of model by coupled-crack. For the aim of quantitative evaluation coupled-crack effect, the mechanics model is constructed to equivalent the strength of coal-rock mass after coupled-crack. Through the accomplishment of equivalent discretization transformation for coal-mass overall-dispersion, the rules of top coal caving/flowing pattern and the articulated relationship of discrete state particles and its influence on caving are revealed. The relationship between caving/flowing capacity of coal-rock mass and the parameters of explosive load and injection water pressure is quantified, forming the technology of coal-rock mass coupled-crack and achieving the effect of quantitative assessment caused by coupled-crack in coal-rock mass under the complex conditions.

英文关键词： strata control;dynamic hazard;multifield coupling;steeply dipping;numerical simulation