摘要
为探究不同温度冲击后煤的热损伤与力学性能变化的相关性,以平煤股份十矿深部煤岩为研究对象,利用伺服万能试验系统、高温恒温箱、非金属超声检测仪和4 K科研级测量相机,开展试验,研究不同温度热冲击作用下的煤岩细观损伤演化及力学特征。结果表明:随热冲击温度增加,煤体产生大量细观可见的损伤,煤岩强度随温度升高呈减弱趋势;煤岩端面裂隙网络盒维数DB可作为定量表征煤岩损伤程度的指标;热冲击温度超过200℃,煤样的破坏由弹脆性向延-塑性转变。热冲击冷却后煤岩损伤具有不可恢复性,因此,工程实践中煤层自然发火熄灭后,仍需关注煤层热损伤造成的力学性质的变化。
In order to study correlation between thermal damage and mechanical performance of coal after thermal shocks at different temperature,with deep coal of Pingmei No.10 Mine as a research object,experiment was conducted by using universal testing machine,constant temperature box,ultrasonic detector and 4 K measuring camera.Meso-damage evolution and mechanical characteristics of coal after thermal shock were studied.The results show that as temperature rises,coal body produces a lot of mesovisible damage,and coal strength weakens.Box dimension DBof fracture network can be used as an index to quantitatively characterize degree of coal damage.When thermal shock temperature exceeds 200℃,destruction of coal samples changes from elastic brittleness to ductile-plastic state,and such destruction after thermal shock cooling is irrecoverable.Therefore,attention still needs to be paid to changes in mechanical properties caused by thermal damage after coal seam spontaneously extinguishes in engineering practice.
作者
齐消寒
马恒
王晓琪
张遵国
吕有厂
QI Xiaohan;MA Heng;WANG Xiaoqi;ZHANG Zunguo;LYU Youchang(College of Safety Science and Engineering,Liaoning Technical University,Huludao Liaoning 125105,China;Key Laboratory of Mine Thermo-motive Disaster&Prevention,Ministry of Education,Huludao Liaoning 125105,China;China Pingmei Shenma Energy and Chemical Industry Group Co.,Ltd.,Pingdingshan Henan 467000,China)
出处
《中国安全科学学报》
CAS
CSCD
北大核心
2020年第12期85-92,共8页
China Safety Science Journal
基金
国家自然科学基金资助(51704147)
辽宁省教育厅青年基金资助(LJ2017QL002)。
关键词
热冲击
深部煤岩
细观损伤
力学特性
盒维数
超声波
thermal shocks
deep coal
meso-damage
mechanical characteristics
box dimension
ultrasonic
