基于能量耗散的煤岩三轴受压损伤演化特征研究  

Study on triaxial compression damage evolution characteristicsof coal based on energy dissipation

作　　者：张尧 李波波[1,2,3] 许江 高政[1] 陈帅 王斌 ZHANG Yao;LI Bobo;XU Jiang;GAO Zheng;CHEN Shuai;WANG Bin(College of Mining,Guizhou University,Guiyang,Guizhou 550025,China;National and Local Joint Laboratory of Engineering for Effective Utilization of Regional Mineral Resources from Karst Areas,Guizhou University,Guiyang,Guizhou 550025,China;Guizhou Key Laboratory of Comprehensive Utilization of Non-metallic Mineral Resources,Guiyang,Guizhou 550025,China;State Key Laboratory of Coal Mine Disaster Dynamics and Control,Chongqing University,Chongqing 400044,China)

机构地区：[1]贵州大学矿业学院,贵州贵阳550025 [2]贵州大学喀斯特地区优势矿产资源高效利用国家地方联合工程实验室,贵州贵阳550025 [3]贵州省非金属矿产资源综合利用重点实验室,贵州贵阳550025 [4]重庆大学煤矿灾害动力学与控制国家重点实验室,重庆400044

出　　处：《岩石力学与工程学报》2021年第8期1614-1627,共14页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(52064007,51804085,51911530203)。

摘　　要：在煤矿资源的地下开采工程活动中,煤岩处于轴压、围压和瓦斯气体相互耦合的复杂应力环境。为探究煤岩受压过程中的损伤变形及能量演化特征,利用含瓦斯煤热-流-固耦合三轴伺服渗流试验装置,开展煤岩在不同围压及不同瓦斯压力条件下的三轴压缩试验研究。基于连续损伤力学理论,从能量角度理论推导由非均质威布尔函数、能量耗散函数及塑性应变函数构成的损伤应力-应变函数,并在此基础上建立基于能量耗散的煤岩损伤本构模型。研究结果表明:(1)不同围压、不同瓦斯压力下煤岩应力-应变变化趋势及塑性变形行为具有阶段性特征。(2)对应不同的变形破坏阶段煤岩的能量演化趋势呈阶段性变化,应力峰值点处煤岩吸收的总能量随围压的增大而增大,弹性能及耗散能也呈现增大的趋势;随着瓦斯压力的上升,煤岩吸收的总能量和弹性能在应力峰值点处呈下降趋势,耗散能呈上升趋势。(3)构建围压及瓦斯压力效应下基于能量耗散的煤岩损伤本构模型,并通过试验验证该模型具有较好的合理性。(4)不同围压及瓦斯压力下煤岩能量耗散与损伤演化均呈“S”型演化趋势。In the underground mining engineering activities of coal resources,coal is in the complex stress environment with the coupling of the axial pressure,the confining pressure and the gas pressure.In order to explore the damage deformation and energy evolution characteristics of coal during the compression process,the triaxial compression test of coal under different confining pressures and different gas pressures is carried out by using a triaxial servo-controlled seepage device.Based on the theory of continuous damage mechanics,the damage stress-strain function composed of heterogeneous Weibull function,energy dissipation function and plastic strain function is deduced theoretically from the angle of energy,and the plastic damage constitutive model of coal based on energy dissipation is constructed.The results show that the change trend of stress-strain and plastic deformation behavior of coal under different confining pressures and different gas pressures have stage characteristics.Corresponding to different deformation and failure stages,the energy evolution trend of coal and rock shows periodic changes. It isalso shown that,at the stress peak point,the total energy absorbed by coal as well as the elastic energy and thedissipated energy increases with increasing the confining pressure. However,the total energy absorbed by coal andthe elastic energy decrease with increasing the gas pressure,while the dissipated energy increases. A plasticdamage constitutive model of coal based on energy dissipation under the effect of the confining pressure and thegas pressure is constructed,and the rationality of the model is verified by experiments. Under different confiningpressures and gas pressures,the energy dissipation and damage evolution of coal experience a S type evolution trend.

关 键 词：采矿工程 煤岩 三轴压缩 能量耗散 塑性应变 损伤变形 

分 类 号：TD32[矿业工程—矿井建设]