摘要
为有效预防煤岩动力灾害,利用含瓦斯煤热-流-固耦合三轴伺服渗流试验装置对煤岩进行三轴压缩试验,研究三轴应力下煤岩的变形破坏特征及损伤过程中的能量演化机制;建立煤岩损伤本构模型;构建损伤-能量耦合数学表达式。结果表明:不同围压下煤岩偏应力-应变曲线的变化趋势基本一致;煤岩在变形破坏过程中,能量转换形式随变形破坏规律呈现阶段性变化;围压对煤岩的能耗特征有较大的影响,煤岩吸收的总能量、弹性能、耗散能的增长速率均随围压的增大而增大,且在峰值偏应力点处,随着围压的增大,临界破坏点总能量、储能极限、临界破坏点耗散能线性增大;能量耗散是造成煤岩内部结构产生损伤的主要原因,耗散能随损伤变量的增大总体上呈S型变化。
In order to prevent coal dynamic disasters effectively,triaxial servo-controlled seepage equipment of thermo-fluid-solid coupling was used for a triaxial compression test of coal to study its deformation and failure characteristics under triaxial stress and mechanism of energy evolution in process of damage.Then,a constitutive model of coal damage was established and mathematical expression of damage-energy coupling was constructed.The experimental results show that change trend of partial stressstrain curve of coal under different confining pressure is basically consistent.Its energy conversion form shows a periodic change in accordance with deformation and failure rules.Confining pressure has a great influence on energy consumption characteristics,since as it increases,the growth rate of total energy absorbed by coal,elastic performance and dissipation energy will also increase,and at peak partial stress point,with its increase,total energy,storage limit and dissipation energy of critical failure point would increase linearly.Energy dissipation is the main cause of damage to internal structure of coal,and it will change in an S type with an increase of damage variables.
作者
李波波
张尧
任崇鸿
杨康
李建华
许江
LI Bobo;ZHANG Yao;REN Chonghong;YANG Kang;LI Jianhua;XU Jiang(College of Mining,Guizhou University,Guiyang Guizhou 550025,China;National Local Joint Engineering Laboratory for Efficient Utilization of Dominant Mineral Resources in Karst Mountain Area,Guizhou University,Guiyang Guizhou 550025,China;State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology,Shandong University of Science and Technology,Qingdao Shandong 266590,China;State Key Laboratory of Coal Mine Disaster Dynamics and Control,Chongqing University,Chongqing 400044,China)
出处
《中国安全科学学报》
CAS
CSCD
北大核心
2019年第10期98-104,共7页
China Safety Science Journal
基金
国家自然科学基金资助(51804085,51911530203)
贵州省科技计划项目(黔科合平台人才[2018]5781号).
关键词
三轴应力
煤岩损伤
力学特性
本构模型
能量特征
triaxial stress
coal damage
mechanical characteristics
constitutive model
energy characteristics
