基于融和残留效应的岩石的莫尔-库伦强度标准的校正方法
Yang Liu1,2, Xiangzhen Meng3, Huimei Zhang4
1School of Geology and Environment, Xi'an University of Science and Technology, Xi'an, 710054, China.
Scientific reports
|December 28, 2024
概括
这项研究开发了一种新的岩石构成模型,并修订了莫尔-库伦 (M-C) 强度标准,以考虑融周期和残余应力. 该模型准确地反映了岩石变形和故障,这对于寒冷地区工程至关重要.
科学领域:
- 地质技术工程 地质技术工程
- 岩石力学 岩石力学 岩石力学
- 材料科学 材料科学 材料科学
背景情况:
- 现有的岩石损伤构成模型往往忽略了残余应力.
- 冰解效应在冷区工程中至关重要,但未被充分纳入当前模型.
- 岩石断裂在限制压力下从脆性转变为塑料,在断裂后具有残余强度.
研究的目的:
- 建立一个构成模型和损害变量,用于受融周期和限制压力的岩石.
- 开发一个修订的莫尔-库伦 (M-C) 强度标准,将融效应和残余应力纳入其中.
- 为了验证模型在预测岩石变形和故障过程中的准确性.
主要方法:
- 基于微元件在冷解和负载下故障特征的总损坏变量和构成模型的开发.
- 建立一个修订的M-C强度标准,考虑冷解周期和残留效应.
- 使用三轴测试数据进行验证,将理论曲线与实验结果 (R2 ≤ 0.6) 和标准数据与测试数据 (差异<25%) 进行比较.
主要成果:
- 开发的构成模型准确地反映了岩石变形和失败的整个过程.
- 增加冷解周期会降低岩石强度 (在40个周期后减少60%以上),并增加变形.
- 限制压力的增加增加了岩石强度 (超过80%的增加从0到6MPa) 和变形.
结论:
- 修订后的M-C强度标准,包括冷解和残留效应,为岩石元素故障分析提供了合理的基础.
- 这种方法为德鲁克-普拉格 (D-Prager) 标准提供了一个更灵活和更现实的替代方案,特别是在寒冷的地区.
- 该模型的验证证实了其适用于在不同的环境条件下描述岩石极限状态的适用性.
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