Analysis of compressive fracture in rock using statistical techniques: Part I. A non-linear rule-based model
Analysis of compressive fracture in rock using statistical techniques: Part I. A non-linear rule-based model
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DOI：
10.1016/s0148-9062(98)00008-4
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发表时间：
1998-10-01
影响因子：
7.2
通讯作者：
Cook, NGW
中科院分区：
文献类型：
--
作者：
Blair, SC;Cook, NGW
本文提出了一种新的非线性脆性材料压缩断裂的规则模型，并用于研究裂纹在颗粒尺度上的成核和扩展。我们用该模型模拟了岩石试样的单轴压缩试验，结果强调了裂纹相互作用在岩石压缩拉伸断裂中的重要性，即使在低裂纹密度下。此外，该模型产生的非线性应力-应变行为类似于在实验室测试中观察到的。我们已经分析了应力-应变行为，并发现在这些模拟中，断裂以以下方式发生。首先，初始损伤是由随机开裂引起的。当大约15%的位点断裂时，裂纹开始相互作用并聚结以形成较大的裂纹，其然后可以传播阵列长度的显著部分。裂纹扩展之后可能是裂纹扩展，随后在瓣尖前方形成损伤区。最后，一系列的裂缝会连接起来，形成断裂，最终导致故障。该模型表明，抗压强度随着尺寸的增加而降低，遵循幂律关系与艺术指数，这是从实验室研究确定的相似，和现场测试结果。该模型还可以将岩石组构的强度和几何形状的非均匀性，在第二部分中，该模型被用来研究如何在这些参数的微尺度非均匀性影响拉伸裂纹扩展压缩。出版社：Elsevier Science Ltd
A new non-linear rule-based model for the fracture in compression of heterogeneous brittle materials such as rock is presented and used to study crack nucleation and propagation at the grain scale, We have used the model to simulate uniaxial compression tests of rock samples and results underscore the importance of crack interaction in extensile cracking of rock in compression even at low crack densities. Moreover, the model produces non-linear stress-strain behavior similar to that observed in laboratory tests. We have analyzed the stress-strain behavior and found that in these simulations fracture occurs in the following way,. First, initial damage occurs by random cracking. When approximately 15% of the sites are broken, cracks start to interact and coalesce to form larger cracks which then may propagate a significant fraction of the array length. Crack extension may be followed by crack nn est and subsequent formation of a damage zone ahead of a clack tip. Finally, a series of cracks will link and form a fracture that eventually causes failure. The model shows decreasing compressive strength with increasing size following a power-law relationship with art exponent that is similar to that determined from the study of laboratory, and field-test results. The model can also incorporate heterogeneity in the strength and geometry of rock fabric, in part II, the model is used to investigate how microscale heterogeneity in these parameters affects extensile crack growth in compression. Published by Elsevier Science Ltd.