加载速率对Ⅰ型加载下页岩断裂行为的影响（英文）
发布时间：2022-07-02 15:33
本研究从动态和静态加载条件下考察了加载速率对页岩断裂行为的影响。在纯I型加载条件下采用分离式的SHPB杆和INSTRON1346伺服试验机对页岩试样进行了测试。在测试过程中,使用高速摄影仪和声发射采集系统分别对试样破坏过程和试样破坏产生的声发射信号进行监测,同时,通过裂纹扩展仪（CPG）测量裂纹扩展速度。结果表明,页岩的断裂韧度和裂纹扩展速度与加载速率呈正相关。在静态载荷条件下建立了断裂韧度和裂纹扩展速度与加载速率之间的关系。另外,还对不同加载速率下的声发射信号特征进行了分析。发现随着加载速率的增加,微裂纹扩展产生的声发射信号减小,同时,声发射累积计数的突变点随着加载速率的增加而向前移动,这表明低加载速率下页岩破裂产生的声发射信号主要来自微裂纹的萌生和扩展,而高加载速率下则主要来自宏观大尺度裂纹的形成。根据声发射信号的分析结果,探讨了引起页岩断裂韧度和裂纹扩展速度随加载速率变化的断裂机理。
【文章页数】：15 页
【文章目录】：
1 Introduction
2 Experimental program
2.1 Testing method and specimen preparation
2.2 Loading apparatus and crack propagation measurement techniques
2.2.1 High-speed digital image correlation technique
2.2.2 Crack propagation velocity measurement system
2.2.3 Acoustic emission system
3 Result and discussion
3.1 Mechanical behavior of shale with different loading rates
3.2 Fracture toughness of shale with different loading rates
3.3 Crack propagation velocity of shale with different loading rates
3.4 AE characteristics
4 Conclusions
Contributors
Conflict of interest
本文编号：3654618
【文章页数】：15 页
【文章目录】：
1 Introduction
2 Experimental program
2.1 Testing method and specimen preparation
2.2 Loading apparatus and crack propagation measurement techniques
2.2.1 High-speed digital image correlation technique
2.2.2 Crack propagation velocity measurement system
2.2.3 Acoustic emission system
3 Result and discussion
3.1 Mechanical behavior of shale with different loading rates
3.2 Fracture toughness of shale with different loading rates
3.3 Crack propagation velocity of shale with different loading rates
3.4 AE characteristics
4 Conclusions
Contributors
Conflict of interest
本文编号：3654618
本文链接：https://www.wllwen.com/jingjilunwen/jianzhujingjilunwen/3654618.html
