【作者】 李明；

【导师】 茅献彪；

【作者基本信息】 中国矿业大学 ， 工程力学， 2014， 博士

【摘要】 “三高一扰动”（即高地应力、高地温、高岩溶水压和强烈开采扰动）是煤矿开采进入深部后岩体所必然面临的复杂恶劣环境，给煤矿安全生产提出了极具挑战性的研究课题。与常温静载条件相比，处于高温及高应变率复杂力学环境下的岩石力学性能及破坏机理具有本质的差异，因此，研究高温及冲击载荷作用下煤系岩层力学特性及损伤演化及破裂机理，对于深部矿井高效安全生产具有重要意义。本文以典型的煤系砂岩层为研究对象，综合应用实验研究、理论分析等方法与手段，借助于先进的测试技术与分析手段，结合现代力学理论，对高温及高应变率作用下煤系砂岩的力学特性及损伤破裂机理进行了系统的研究，取得了如下创新性成果：（1）借助于分离式霍普金森压杆（SHPB）试验系统，对不同应变率下煤系砂岩的单轴压缩特性进行了测定，得到了煤系砂岩的应力-应变曲线，动态弹性模量、峰值应力、峰值应变随应变率的变化规律，并给出了应变率对煤系砂岩破坏与能量耗散特征的影响规律。（2）借助于SHPB试验系统、GWD-02A温度加载及控制系统，系统研究了高温作用后煤系砂岩力学特性及破坏特征的应变率效应，得到了高温作用对高应变率下煤系砂岩的应力-应变曲线、动弹模、峰值应力、峰值应变的影响规律，并给出了试样的破坏特征、能量耗散等随温度及温度加载速率的变化规律。（3）基于试样物质组分及断口形貌特征的X射线衍射试验及扫描电镜试验，得到了高应变下煤系砂岩的组分及晶粒尺寸随温度及加温速率的变化规律，探讨了试样的损伤破裂模式随应变率、温度的变化特征，一定程度上揭示了高温及高应变率作用下煤系砂岩宏观破裂特征的微观机制。（4）依据岩石的损伤断裂理论，分别建立了考虑温度作用、应变率效应的煤系砂岩损伤演化及本构方程，并依据煤系砂岩的应力应变试验曲线确定了方程的具体参数。经比较，所建立的煤系砂岩本构方程与试验结果具有很好的印证性。研究成果可为煤系岩层结构的破坏规律及工程稳定性分析提供重要参考。更多还原

【Abstract】 Three-high-one-disturbance, which means high earth temperature, the highcrustal stress, the high karst water and strong mining disturbance, is the complex andextreme environment the rock should face when mining in deep, which brings greatchallenge-subject to coalmine safety production. Compared with normal static load,there are completely differences on mechanical properties and failure mechanism ofrock in complex mechanical environment, which are high temperature and high strainrate. Therefore, it is great influence on high-efficient mining production, which makesanalyzing on rock mechanical properties, damage evolution and failure mechanismunder high temperature and impact loading. In this paper, sandstone in coal measuresis the main study object, and experiment researched measure and theory analyzed isthe method and means. With the help of advanced testing technology and analysismethods, combined with modern mechanical theory, we make systematic study onthis condition, and obtain some innovative achievements(1) By using split hopkinson pressure bar testing system (SHPB), we makemeasurement on uniaxial compression of sandstone in coal measures in differentstrain rate. Then we obtain its change rules on stress-strain curve, dynamic elasticitymodulus, peak stress and peak strain, and put forward the influence between strainrate to its damage and energy dissipation.(2)By using SHPB testing system, GWD-02A temperature loading and controlsystem, we make systematic research on its mechanical properties and thestrain-rate-effect of damage characteristics. Then we obtain these rules under hightemperature to high strain rate, and put forward the influence between the sampledestruction and energy dissipation to temperature and its loading rate.(3)Based on the sample material composition and fracture morphologycharacteristics, we make experiment with x-ray diffraction and scanning electronmicroscope. Then we obtain its composition and grain size changing with temperatureand its loading rate, and analyze the sample’s damage mode changing with strain rateand temperature, which reveals the microcosmic fracture mechanism at a certainextent.(4)According to rock fracture theory, we build its fracture evolution andconstitutive equation by considering temperature and strain rate effect, and confirmthe detailed parameter by the experimental curve. Compared with it, there is very good corroborating between the constitutive equations to experiment data.The result should be the main reference to the structure damage of sandstone incoal measures and stability analysis for engineering.更多还原