摘要
为了研究单轴压缩作用下预制裂纹对岩石的力学性能、声发射和能量演化的影响,通过室内试验数据反演PFC2D模型的力学参数,然后在数值模拟的基础上分析不同倾角和长度的预制裂纹对岩石力学特性的影响。结果表明:预制裂纹倾角越大,岩石的峰值应力和峰值应变越大,而弹性模量和变形模量也会随着倾角的增大而增大;预制裂纹长度增加时,峰值应力、峰值应变、弹性模量和变形模量不断减小。在预制裂纹倾角为0°,15°,30°,45°时,微裂纹计数波动较大,在60°,75°,90°时计数较为稳定。预制裂纹倾角为0°,15°,30°,45°,60°时,裂纹以翼型裂纹扩展为主,在75°和90°时,并没有出现翼型裂纹,而是在岩体上出现大量的微破裂,在轴向应力的作用下,这些微破裂逐渐贯通,造成剪切破坏。预制裂纹倾角在0°,15°,30°,45°时岩石内部损伤的出现早于60°,75°,90°的,并且弹性储能极限随着预制裂纹倾角的增大而增大。
In order to study the effects of prefabricated cracks on the mechanical properties,acoustic emis‐sion and energy evolution of rock under uniaxial compression,the mechanical parameters of PFC2D numeri‐cal simulation model were inverse performed in laboratory experiments,and then the effects of different dip angles and lengths of prefabricated cracks on rock properties were analyzed on the basis of numerical simu‐lation.The experimental results show that the peak stress and peak strain of rock increase with the increase of prefabricated crack angle,and the elastic modulus and deformation modulus also increase with the in‐crease of prefabricated crack angle.However,when the length increased,the peak stress,peak strain,elastic modulus and deformation modulus decreased continuously.When the prefabricated crack dip angle was 0°,15°,30°,45°,the microcrack count fluctuates greatly,and when the prefabricated crack dip angle was 60°,75°,90°,the microcrack count was stable.At the same time,when the dip angle of prefabricated crack was 0°,15°,30°,45°,60°,the airfoil crack is the main crack growth,while when the dip angle of prefabricated crack is 75°,90°,there is no airfoil crack,but a large number of micro-cracks appear on the rock mass.Un‐der the action of axial stress,these micro-cracks are gradually connected,resulting in shear failure.When the prefabricated crack angle is0°,15°,30°,45°,the internal damage of rock appears earlier than that of 60°,75°,90°,and the elastic storage limit increases with the increase of the prefabricated crack angle.
作者
王云飞
马勇超
董贺
WANG Yunfei;MA Yongchao;DONG He(School of Civil Engineering,Henan Polytechnic University,Jiaozuo 454000,Henan,China)
出处
《河南理工大学学报（自然科学版）》
CAS
北大核心
2023年第6期157-166,共10页
Journal of Henan Polytechnic University（Natural Science）
基金
国家自然科学基金资助项目(U1604142)。
关键词
预制裂纹
力学性能
能量演化
PFC2D
prefabricated crack
mechanical property
energy evolution
PFC2D
