论文部分内容阅读
目前采用传统颗粒体模型较难表征岩石内部不规则矿物颗粒的结构特征。以颗粒流理论及PFC程序为平台,采用平面黏结接触模型,构建能反映矿物颗粒结构特征的岩石厚壁圆筒数值模型,从细观力学角度深入探究岩石厚壁圆筒试样在不同内外部围压条件下的破裂机制与规律。研究表明:当内部围压为0时,试样张拉型微破裂占主导优势;层状剥离的破碎颗粒体以轴线为中心形成近似对称的“V”型破坏区域。当内部围压不为0时,随着内部围压不断增大,试样承受的极限外部围压逐渐增大;试样剪切型微破裂逐渐占主导优势,以轴线为中心产生的近似对称的“V”型破坏区域逐渐消退,破坏逐渐从内径岩壁向各个方向扩展。无论内部围压是否为0,试样外部围压、外部体应变等破坏参量演化曲线均可近似划分为3个阶段。
At present, it is difficult to characterize the structural features of irregular mineral particles in the rock using the traditional particle model. Based on the particle flow theory and the PFC program, a planar cohesive contact model was used to construct a thick-walled cylinder numerical model that can reflect the structural features of the mineral particles. From the perspective of meso-mechanics, the thick- Rupture Mechanism and Rules under Confining Pressure. The results show that when the internal confining pressure is 0, the tensile strain of microcracks dominates. The delaminated crushed particles form an approximately symmetrical “V” type failure zone centering on the axis. When the internal confining pressure is not 0, as the internal confining pressure increases, the ultimate external confining pressure increases gradually. The specimen shear micro-fracture gradually dominates and the axis-centered approximate symmetry Of the “V” type destruction area gradually subsided, the destruction gradually expanded from the inner diameter of the rock wall in all directions. Regardless of whether the internal confining pressure is 0 or not, the evolvement curves of failure parameters such as the external confining pressure and external body strain of the specimen can be roughly divided into three stages.