Analysis of Rock Damage Characteristics Based on Particle Discrete Element Model
Analysis of Rock Damage Characteristics Based on Particle Discrete Element Model
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DOI：
10.1007/s10706-017-0363-0
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发表时间：
2017-09
影响因子：
1.7
通讯作者：
Zhen-long Zhao;Xiao Wang;Zhi-jie Wen
中科院分区：
文献类型：
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作者：
Zhen-long Zhao;Xiao Wang;Zhi-jie Wen
岩石是由各种尺寸的矿物组成的非均质介质。在外荷载作用下，岩体中微缺陷的产生、扩展和聚结决定了岩石的宏观变形和破裂。为了了解岩石的损伤规律并揭示动态破坏的演化过程，建立了基于颗粒流代码的单轴压缩模型。分析了岩石损伤的声发射和能量特征，讨论了岩石损伤本构模型。岩石单轴压缩过程中，声发射事件经历了相对安静、突然增加和急剧减少三个时期，分别对应应力应变曲线中的压实弹性变形阶段、屈服阶段和峰后阶段。在达到屈服应力之前，键能和应变能所占的比例较大。摩擦能占总能量的比例很小，并且它们之间存在着相互关系。基于摩擦能的本构模型比基于声发射参数的本构模型更能反映应力应变的变化。
Rock is a heterogeneous medium that is composed of minerals of various sizes. Under the action of external loads, the generation, propagation and coalescence of microdefects in the rock mass determines the macroscopic deformation and fracture of rock. To understand the damage law of rock and to reveal the evolution of dynamic failure, a uniaxial compression model was established based on particle flow code. Acoustic emission and energy characteristics of rock damage were analyzed, and the damage constitutive models of rock were discussed. During rock uniaxial compression, acoustic-emission events undergo a relatively quiet, sudden increase and sharp decrease for three periods, which corresponds to the compaction and elastic deformation stage, yield stage and post-peak stage in the stress–strain curve. Before the yield stress is reached, the proportion of bond and strain energies is larger. Friction energy accounts for a small proportion of the total energy, and a reciprocal relationship exists between them. The constitutive model that is based on friction energy can better reflect the variation in stress and strain, then the constitutive model based on acoustic-emission parameters.