页岩岩在高速冲击负荷和不同的限制压力下形成孔缩和裂纹演变
Jiawei Wang1, Chuanjie Zhu2, Cong Ma1
1Faculty of Safety Engineering, China University of Mining and Technology, Xuzhou, 221116, Jiangsu, China.
Scientific reports
|February 22, 2025
概括
在限制压力下对页岩的高速冲击会导致明显的孔隙紧缩和裂变化. 较高的压力减少孔积和表面积,影响页岩失效模式和弹性特性,这对于页岩气提取至关重要.
科学领域:
- 地力学和材料科学 地力学和材料科学
- 石油工程是石油工程中的一个.
背景情况:
- 高速冲击载荷显著影响页岩的机械行为,特别是孔隙结构和裂演变.
- 了解这些影响对于优化页岩气提取技术至关重要.
研究的目的:
- 研究不同限制压力对孔隙紧缩和在高速冲击下页岩中的微观裂演变的影响.
- 分析受冲击负荷影响的页岩样本的孔隙结构,特定表面积和故障模式的变化.
主要方法:
- 分裂霍普金森压力杆 (SHPB) 实验在江西 (JX) 和四川 (SC) 页岩样本上进行,限制压力为0,5,15和25MPa.
- 冲击后分析包括低温吸附 (LTNA),侵入孔径测量 (MIP) 和环境扫描电子显微镜 (ESEM).
- 评估不同压力条件下的孔积,特定表面积和故障机制.
主要成果:
- 限制压力显著减少了JX和SC页岩的总孔积 (TPV) 和总特定表面积 (TSSA).
- 宏孔比中孔更容易受到限制压力的影响.
- 页岩样本在较低的限制压力 (0-15MPa) 时表现出脆性剪切损伤,在25MPa时表现出脆性-柔性过渡 (BDT),弹性模量增加.
结论:
- 限制压力在冲击负荷下的页岩中孔隙紧缩和裂演变中发挥着关键作用.
- 观察到的孔隙结构和故障模式的变化为页岩对动态应力反应提供了洞察力.
- 这些发现对于提高动态页岩气生产过程的效率和控制至关重要.
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