超声振动作用下青砂岩细观损伤演化规律及断裂能利用效率研究  

Study on the evolution law of micro damage and utilization efficiency of fracture energy in green sandstone under the action of ultrasonic vibration

作　　者：赵环帅 潘永泰[1,2] 余超 曹行健[1,2] 乔鑫 ZHAO Huanshuai;PAN Yongtai;YU Chao;CAO Xingjian;QIAO Xin(School of Chemical and Environmental Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China;Engineering Research Center for the Mine and Municipal Solid Waste Recycling,China University of Mining and Technology(Beijing),Beijing 100083,China)

机构地区：[1]中国矿业大学(北京)化学与环境工程学院,北京100083 [2]中国矿业大学(北京)矿山与城市固废资源化工程研究中心,北京100083

出　　处：《岩石力学与工程学报》2024年第7期1646-1661,共16页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金面上项目(52074308)。

摘　　要：超声振动破岩技术具有显著优势和发展潜力,为研究超声振动作用下岩石细观损伤演化规律及断裂能利用效率,结合物理试验与细观参数标定,建立青砂岩宏-细观力学响应关系,分析超声振动作用下接触力场、破坏特征及裂纹特点的演化规律,研究断裂能利用效率。研究结果表明:(1)在激励初期,最大接触力集中于青砂岩上端,而内部接触力较小,呈现出明显的“V”型。随着激励增加,接触力不断增大,原来杂乱分布的接触力逐渐呈规则分布,以波浪状向下端传递。(2)青砂岩破坏过程分为裂纹萌生、扩展、贯通3个阶段,最终破坏呈现出单侧剪切破坏特征。在相同振动频率下,随着振幅增加,青砂岩破坏块体与裂纹数量总体上呈斜向上增长的趋势;在相同的振幅下,随着振动频率增加,青砂岩的破坏块体与裂纹数量呈波动趋势。(3)剪切裂纹声发射次数最大值出现的时间最早,拉伸裂纹声发射次数最大值出现的时间次之,拉伸与剪切裂纹累积裂纹数量相等出现的时间最晚。超声振动激励初期,青砂岩以剪切裂纹为主,最终以拉伸裂纹为主,拉伸作用在破坏过程中起主要作用。在此过程中,裂纹主要是以超声振动载荷平行的方向扩展为主,而水平方向裂纹扩展较少。(4)在相同振动频率下,随着振幅增加,青砂岩断裂能利用效率呈现出下降并波动的趋势;在相同的振幅下,随着振动频率增加,青砂岩断裂能利用效率呈波动的趋势,断裂能利用效率范围为9.448%~12.456%。研究结果可为岩石破碎工艺参数的合理选择提供参考。The rock-breaking technology of ultrasonic vibration has significant advantage and development potential.In order to study the evolution law of micro damage and utilization efficiency of fracture energy in rock under the action of ultrasonic vibration,combined with physical experiment and microscopic parameter calibration,the relationship of macro and micro mechanical responses in green sandstone was established.The evolution laws of contact force field,failure characteristics and crack characteristics under the action of ultrasonic vibration were analyzed,and the utilization efficiency of fracture energy was studied.The results show that:(1)in the initial stage of excitation,the maximum contact force is concentrated in the upper end of the green sandstone,while the internal contact force is relatively small,showing an obvious“V”shape.With the increase of the excitation,the contact force continues to increase,and the original disorderly distribution of the contact force is gradually distributed in the regular distribution,transmitting to the lower end in the form of wave.(2)The failure process of green sandstone can be divided into the three stages of emergence,expansion,and penetration,and the final failure is characterized by unilateral shear failure.Under the same vibration frequency,with the increase of amplitude,the number of damaged blocks and cracks in green sandstone generally shows the upward sloping trend.Under the same amplitude,with the increase of vibration frequency,the number of damaged blocks and cracks in the green sandstone shows the up and down fluctuating trend.(3)The order of crack generation time is as follows:maximum value of shear crack(acoustic emission),maximum value of tensile crack(acoustic emission),equal cumulative crack(tensile and shear cracks).In the initial stage of ultrasonic vibration excitation,the green sandstone is dominated by shear cracks,and eventually by tensile cracks,and the tensile effect plays the major role in the failure process.During this process,the cracks m

关 键 词：岩石力学 青砂岩 超声振动 颗粒流模拟 损伤演化 裂纹 断裂能 

分 类 号：TU45[建筑科学—岩土工程]