Progressive deformation and pore network attributes of sandstone at in-situ stress states using computed tomography
Progressive deformation and pore network attributes of sandstone at in-situ stress states using computed tomography
复制标题
DOI：
10.1016/j.engfracmech.2021.107833
复制
发表时间：
2021-06
影响因子：
5.4
通讯作者：
B. Mahanta;V. Vishal;N. Sirdesai;P. Ranjith;T. Singh
中科院分区：
文献类型：
--
作者：
B. Mahanta;V. Vishal;N. Sirdesai;P. Ranjith;T. Singh
了解砂岩的微观破坏机制对于各种工程项目尤为重要。目前的研究研究了基于实时高分辨率微型计算机断层扫描（m-CT）的砂岩在无侧限轴向压缩下的微观破坏属性。在不同的载荷条件下（零载荷、25%、50%、75%峰值载荷和峰值破坏载荷）对砂岩样本进行了分析，以分析其对各种岩石物理性质的影响，如总孔隙、连通孔隙、不连通孔隙、微裂缝发育以及不同孔隙网络属性（如孔隙半径、孔隙体积、孔隙配位数（CN）、喉道半径和喉道长度）。这样的研究使我们能够探索原位压缩下砂岩内部破坏的演变。结果显示，在峰值载荷达到 50% 后，砂岩中出现了宏观裂缝，并且各种孔隙网络属性呈增加模式。然而，随着加载阶段的增加，不连通的孔隙逐渐减少。最终得到有效孔隙度砂岩的曲折度与配位数之间存在负相关关系。
Understanding the mechanism of microscopic failure of sandstone is exceptionally crucial for various engineering projects. The current study investigates the real-time high-resolution micro-computed tomography (m-CT) based microscopic failure attributes of sandstone under unconfined axial compression. Specimens of sandstone were analysed under varying loading conditions (zero load, 25%, 50%, 75% of the peak loads, and at peak failure loads) for analysing their effects on various petrophysical properties such as total pores, connected pores, non-connected pores, development of microfractures, and different pore network attributes such as pore radius, pore-volume, pore coordination number (CN), throat radius and throat channel length. Such an investigation enables us to explore the evolution of failure within sandstone under in-situ compression. The results showed the appearance of macrofractures and an increasing pattern of various pore-network attributes in the sandstone after 50% of the peak load. However, the non-connected pores gradually decreased with the rising loading stages. Finally, a negative correlation was obtained between tortuosity of sandsone with effective porosity and coordination number.