摘要
针对深部煤层自身高温对深部原位人工破煤技术产生的影响,以辽宁阜新盆地的长焰煤为研究对象,为煤样赋予多个初始温度并进行液氮循环冻融,通过卸载后煤样表面节理宽度、整体孔隙量、单轴抗压强度的变化值,研究煤样结构损伤的物理性质与力学性质。并建立高温煤体循环冻融力学模型,揭示液氮循环冻融所产生的温度应力对不同初始温度煤样结构损伤的作用机理。结果表明:不同初始温度煤样在经过液氮循环冻融后,煤样整体结构均有不同程度损伤,初始温度越高,产生的温度应力越大,煤样物理性质与力学性质的劣化程度也越大,宏观破坏周期越短。
Aiming at the problem that the high temperature of deep coal seam will affect the deep in-situ artificial coal breaking,the long flame coal in Fuxin Basin of Liaoning Province is taken as the research object,and the coal sample is given multiple initial temperatures and subjected to liquid nitrogen cycle freezing and thawing.The physical and mechanical properties of coal sample structure damage are studied by the change values of joint width,overall pore volume and uniaxial compressive strength of coal sample surface after unloading.The mechanical model of high temperature coal freeze-thaw cycle is established to reveal the mechanism of temperature stress caused by liquid nitrogen freeze-thaw cycles on the structural damage of coal samples at different initial temperatures.The results show that the overall structure of coal samples with different initial temperatures has different degrees of damage after liquid nitrogen cycle freeze-thaw.The higher the initial temperature,the greater the temperature stress,the greater the deterioration of physical and mechanical properties of coal samples,and the shorter the macroscopic failure cycle.
作者
李和万
刘戬
王来贵
郭鹏
于洋
任天娇
LI Hewan;LIU Jian;WANG Laigui;GUO Peng;YU Yang;REN Tianjiao(Department of Mechanics and Science Engineering,Liaoning Technical University,Fuxin 123000,China;Luoyang Construction Service Center,Luoyang 471000,China;China Construction Fifth Engineering Division Corp.,Luoyang 471000,China)
出处
《煤炭工程》
北大核心
2023年第11期142-147,共6页
Coal Engineering
基金
国家自然科学基金青年基金项目(51704142)
国家重点研发计划(2017YFC1503102)
辽宁省博士科研启动基金计划项目(2019-BS-115)。
关键词
流态化开采
原位人工破煤
高煤体冻融
温度应力
力学模型
fluidized mining
in-situ artificial coal breaking
freeze-thaw of high temperature coal
temperature stress
mechanical model
作者简介
李和万(1983-),男,辽宁大连人,副教授,研究方向:煤炭绿色开采工作,E-mail:lhw515ql@163.com。
