摘要
为研究煤岩Ⅰ型静态断裂韧度与研磨破碎后新增表面积的关系,采用中心直裂纹半圆盘试样(NSCB)和1~2mm/0.425~1mm粒径试样进行三点弯曲试验和研磨破碎试验,运用断裂力学及岩石破碎学,从理论分析和室内试验两个方面研究二者之间的关系。理论分析表明:断裂韧度的二次方与研磨破碎后新增表面积的倒数成正比;再以试验数据为依据进行拟合,结果表明:1~2 mm/0.425~1 mm粒径试样研磨破碎后,断裂韧度的二次方与新增表面积的倒数均呈很好的正比关系,其相关系数R2分别为0.974和0.878,说明可以用易于计算的破碎后新增表面积来估算煤的断裂韧度,进而获其表面能,这不仅为煤的断裂韧度测定提供一种新的试验方法,也为更深一步理解突出过程中的能量耗散提供试验依据。
Three-point bending tests and grinding tests were carried out with notched semi-circular bend(NSCB)and 1-2 mm/0.425-1 mm particle size samples,and theoretical analysis was performed based on fracture mechanics and rock fragmentation.The theoretical analysis shows that the second power of the fracture toughness is directly proportional to the reciprocal of the newly added surface area after crushing.The fitting results on the test data also indicate that there is a good proportion between the second power of the fracture toughness and the reciprocal of the newly added surface area of the 1-2 mm/0.425-1 mm particle size samples after grinding,and the correlation coefficient R2 are 0.974 and 0.878 respectively,which shows that the fracture toughness of coal can be estimated by the newly added surface area calculated easily and then the surface energy can be obtained.The research not only provides a new test method for the determination of the fracture toughness of coal but also provides an experimental basis for further understanding of the energy dissipation in the process of outburst.
作者
蔡增辉
黄滚
郑杰
成墙
耿伟乐
CAI Zenghui;HUANG Gun;ZHENG Jie;CHENG Qiang;GENG Weile(State Key Laboratory of Coal Mine Disaster Dynamic and Control,Chongqing University,Chongqing 400044,China;School of Resources and Safety Engineering,Chongqing University,Chongqing 400044,China)
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2021年第8期1570-1579,共10页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学基金资助项目(51674049)。
