不同加载速率下煤体表面变形特性及能量演化特征研究  

Study on deformation characteristics and energy evolution of coal under different loading rates

作　　者：金鹏 刘影[1] 冯俊军 李世庚 曲远方 JIN Peng;LIU Ying;FENG Junjun;LI Shigeng;QU Yuanfang(Civil Engineering and Architecture,Anhui University of Technology,Maanshan 243032,China;Sinosteel Maanshan General Institute of Mining Research Co.,Ltd.,Maanshan 243000,China)

机构地区：[1]安徽工业大学建筑工程学院,安徽马鞍山243032 [2]中钢集团马鞍山矿山研究总院股份有限公司,安徽马鞍山243000

出　　处：《煤矿安全》2024年第8期116-123,共8页Safety in Coal Mines

基　　金：国家自然科学基金资助项目(52104175);中国博士后科学基金面上资助项目(2022M712935)。

摘　　要：通过数字散斑技术(digital image correlation,DIC)研究了不同加载速率下煤体表面应变场演化特征,分析了加载速率对表面变形场演化过程、变形局部化特征及表面变形能密度的影响规律。研究结果表明:加载速率越高,煤体最终破坏形态越充分,煤体破坏模式也由剪切破坏过度为张性破坏;不同量级的加载速率影响了煤体的变形局部化时刻,加载速率越高,煤体变形局部化启动时间所占整体破坏时间的比重越大;加载速率越高,变形局部化前变形能密度增长趋势越明显,表面变形局部化区域能量积聚越多,变形局部化启动时刻应力越大。The digital image correlation(DIC)technology was used to investigate the evolution law of the coal surface strain field under different loading rates and to analyze the influence of loading rate on the evolution of the deformation field,deformation localization,and surface deformation energy density.The experimental results indicate that the higher the loading rate is,the more complete the final failure mode of the coal body,and the failure mode of the coal body also transitions from shear failure to tensile failure;the loading rates of different magnitudes also affect the localization time of coal deformation.The higher the loading rate is,the greater the proportion of the initiation time of coal deformation localization to the overall failure time.The higher the loading rate is,the more obvious the growth trend of deformation energy density before deformation localization,and the more energy accumulates in the surface deformation localization area;the qreater the stress at the start time of deformation localization.

关 键 词：加载速率 煤体表面变形 数字散斑技术 变形能密度 变形局部化 

分 类 号：TD315[矿业工程—矿井建设]