不同倾角单裂隙对非均质岩石失稳演化研究
Instability Evolution of Single Fracture with Different Dip Angles on Heterogeneous Rock
王婷静1
作者信息
- 1. 浙江建设职业技术学院,浙江杭州 311231
- 折叠
摘要
岩体中的裂隙对岩石的力学行为、能量演化和失稳破坏有显著影响.为阐明不同倾角单裂隙对岩石能量演化和失稳破坏机理,基于颗粒流PFC2D方法,建立了不同倾角单裂隙砂质泥岩数值模型,模拟了不同倾角单裂隙下砂质泥岩的单轴压缩试验.研究表明,随着单裂隙倾角变大,砂质泥岩的强度与弹性模量先降低后增大,预制裂纹会影响断裂面的裂纹起始位置,并加速断裂面的形成;声发射事件在岩样破坏前存在小范围沉寂期,该特征可作为岩石破坏的前兆判据;随着裂隙倾角的增大,总能量持续增大,弹性能和耗散能呈现先增加后减小的趋势,倾角 30°时,岩石试样冲击倾向性最弱,有利于降低冲击地压危险,倾角为 90°时,岩石试样冲击倾向性相对最强,不利于冲击地压的防治.
Abstract
Fractures in rock mass have a significant influence on the mechanical behavior,energy evolution and instability fail-ure of rock.To clarify the rock energy evolution and instability failure mechanism of single fracture with different dip angles,based on the particle flow PFC2D method,a numerical model of sandy mudstone with single fracture with different dip angles was established,and the uniaxial compression test of sandy mudstone with single fracture with different dip angles was simulated.The results show that with the increase of single fracture dip angle,the strength and elastic modulus of sandy mudstone decrease first and then increase,and the prefabricated crack will affect the crack initiation position of the fracture surface and accelerate the formation of the fracture sur-face.The acoustic emission event has a small range of quiet period before the rock sample is destroyed,which can be used as a precurs-ory criterion for rock failure.With the increase of fracture dip angle,the total energy continues to increase,and the elastic energy and dissipation energy show a trend of increasing first and then decreasing.When the dip angle is 30°,the rock sample has the weakest im-pact tendency,which is beneficial to reduce the risk of rock burst.When the dip angle is 90°,the rock sample has the strongest impact tendency,which is not conducive to the prevention and control of rock burst.
关键词
PFC2D/岩石/单裂隙倾角/AE/能量演化/弹性能存储率/弹性能释放率Key words
PFC2D/rock/single fracture dip angle/AE/energy evolution/elastic energy storage rate/elastic energy releasing rate引用本文复制引用
基金项目
舟山市科技计划项目(2020C21013)
中交集团科技项目(ZJLJGLTJ5A3JSFW2019011)
出版年
2024
NETL
NSTL
万方数据