在不同控制模式和负载率的单轴压缩试验下,岩石的机械性能
Zhilei He1, Guoli Wu2, Jun Zhu3
1Research Institute of Geotechnical Engineering and Hydraulic Structure, North China University of Water Resources and Electric Power, Zhengzhou, 450046, China. hezhilei@ncwu.edu.cn.
Scientific reports
|January 25, 2024
概括
控制模式显著影响岩石峰后的行为,增强稳定性和可控性. 较低的横向负载率会增加高峰后的波动和故障时间,但不会影响岩石的脆性.
科学领域:
- 地质技术工程 地质技术工程
- 岩石机械学 岩石机械学
- 材料科学 材料科学 材料科学
背景情况:
- 了解不同负载条件下的岩石机械性能对于工程应用至关重要.
- 控制模式和加载速度是影响岩石变形和故障的关键因素.
研究的目的:
- 为了研究轴向应变控制与横向应变控制模式对岩石机械性能的影响.
- 分析负载率对岩石峰后行为和故障特征的影响.
主要方法:
- 在四种岩石类型 (砂石,泥石,花岩) 上进行了单轴压缩测试.
- 在轴应变控制和横应变控制模式下进行了测试.
- 分析了完整的应力-应变曲线,强度,脆性和故障模式.
主要成果:
- 控制模式主要影响高峰后的行为,导致稳定可控的变形 (II类行为).
- 降低横向负载率会增加高峰后曲线波动和故障时间,但不会显著改变脆性.
- 轴应变控制导致分裂失败,而横向应变控制促进剪切失败,特别是在较低的速度.
结论:
- 控制模式和加载率是影响岩石变形和故障特征的关键参数.
- 侧向应变控制提供了一种研究脆性岩石剪切失效机制的方法.
- 这些发现补充了对速度依赖性岩石特性的理解,并为工程设计提供了洞察力.
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