高温花岩在水冷下发生的宏观/微裂变演变和不稳定行为,经过巴西的裂变测试,使用DIC技术进行了DIC技术
Xinghui Wu1, Xu Wu2, Shukun Zhang1
1School of City and Architecture Engineering, Zaozhuang University, Zaozhuang, Shandong, China.
PloS one
|November 29, 2023
概括
高温 (450-600°C) 会降解花岩,降低其抗拉强度和P波速度. 形成微裂,改变应力路径和骨折模式,并提出适合实验数据的模型.
科学领域:
- 地质技术工程 地质技术工程
- 材料科学 材料科学 材料科学
- 岩石机械学 岩石机械学
背景情况:
- 花岩的热损伤演变和稳定性对于地下工程至关重要.
- 高温显著改变岩石特性,影响结构完整性.
- 了解热效应对于预测在极端条件下花岩的行为至关重要.
研究的目的:
- 通过巴西裂变试验,研究花岩的热损伤演变.
- 分析高温对花岩机械性能和稳定性的影响.
- 在热应力下建立P波速度和巴西拉伸强度 (BTS) 之间的关系.
主要方法:
- 巴西的分裂试验是在对高温的花岩样本进行的.
- 采用数字图像相关性 (DIC) 技术来监测菌株演变.
- 进行P波速度测量以评估内部结构变化.
主要成果:
- 在450-600°C以上,巴西拉伸强度和P波速度的下降被观察到.
- 微裂改变了应力传递路径,导致复杂的骨折模式.
- 热损伤影响了P波速度和拉伸强度,在450°C以下和以上有明显的裂发展.
结论:
- 在高温下,花岩的机械性能显著降低.
- 温度诱导的微裂变会影响故障机制和应力分布.
- 一个负指数模型准确地描述了在水冷却下的高温花岩中P波速度和BTS之间的关系.
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