摘要
为探究采动卸荷作用下含瓦斯煤力学特性,利用煤岩气固耦合试验系统对不同瓦斯压力煤体开展增轴压卸围压试验,分析含瓦斯煤强度及变形特征,基于Weibull函数和Mogi-Coulomb强度准则建立考虑瓦斯-荷载耦合的损伤本构模型。研究结果表明:采动卸荷含瓦斯煤经历弹性变形、塑性屈服和峰后破坏阶段,卸荷过程中含瓦斯煤轴向应变增量比线性增加,而环向和体积应变增量比呈3阶段非线性增长趋势;煤体峰值强度、弹性模量和临界破坏卸荷比随瓦斯压力增加而降低;瓦斯-荷载耦合损伤本构模型与试验结果具有较好的一致性,能够准确地描述采动卸荷含瓦斯煤变形破坏特征。研究结果可为揭示含瓦斯煤破坏失稳机制提供理论参考。
In order to investigate the mechanical behavior of gas bearing coal under mining induced unloading,a coal rock gas solid coupling test system is used to conduct axial loading and confining pressure unloading tests on coal specimens under different gas pressures.The strength and deformation characteristics of gas bearing coal are analyzed,and a damage constitutive model considering gas load coupling is established based on the Weibull function and the Mogi-Coulomb strength criterion.The results show that gas bearing coal under mining induced unloading undergoes elastic deformation,plastic yielding,and post peak failure stages.During unloading,the incremental ratio of axial strain increases approximately linearly,whereas the incremental ratios of circumferential strain and volumetric strain exhibit a three stage nonlinear growth trend.The peak strength,elastic modulus,and critical failure unloading ratio decrease with increasing gas pressure.The gas load coupled damage constitutive model shows good agreement with experimental results and accurately describes the deformation and failure characteristics of gas bearing coal under mining induced unloading.These findings provide a theoretical reference for revealing the failure and instability mechanisms of gas bearing coal.
作者
牛心刚
NIU Xin’gang(China Coal Technology and Engineering Group Chongqing Research Institute,Chongqing 400037,China;State Key Laboratory of Coal Mine Disaster Prevention and Control,Chongqing 400037,China)
出处
《中国安全生产科学技术》
北大核心
2025年第12期74-81,共8页
Journal of Safety Science and Technology
基金
国家自然科学基金项目(U21A20110)。
关键词
含瓦斯煤
采动卸荷
变形特性
瓦斯-荷载耦合
本构模型
gas bearing coal
mining unloading
deformation characteristics
gas load coupling
constitutive model
