摘要
裂隙岩体渗流问题是高放核废料地质处置、深部地质能源开采、水利工程以及深地空间开发利用等大型岩体工程中急需解决的关键难题。有别于一般均匀孔隙介质,岩石(体)包含着大量非均匀分布的孔隙、裂隙等结构,其水力传导特性存在显著差异,导致裂隙岩石渗流过程极其复杂。以裂隙砂岩为研究对象,首先采用核磁共振成像技术获取裂隙砂岩内部微观结构图像,然后基于图像数字化技术分割提取裂隙砂岩的主裂隙、次裂隙和岩石基质等微结构特性,构建可真实反映复杂裂(孔)隙结构及非均质水力特性的砂岩数值模型,开展了不同渗流条件及裂隙性状下的裂隙砂岩渗流全过程数值模拟。研究结果表明:裂隙砂岩的渗流速度及出口流量随渗透压力、裂隙开度及裂隙数量增大而增大,随裂隙粗糙度、交叉角度增大而减小。模拟分析得到的渗透系数与试验结果非常接近且变化趋势相同,裂隙岩石渗透系数与裂隙开度、裂隙数量呈正相关性,但与裂隙粗糙度、交叉角度呈负相关性。基于核磁共振图像数字化技术的裂隙砂岩模型可以较好地表征岩石复杂渗流演变特性,为裂隙岩石渗流过程分析提供了可行方法。研究成果为岩体工程渗流分析与控制提供了分析手段和理论指导。
The issue of seepage in fractured rock masses has emerged as a crucial technical challenge in large-scale rock mass engineering projects,such as geological disposal of high-level nuclear waste,deep geological energy mining,hydraulic engineering,and deep underground space exploration.Unlike uniform porous media,rocks contain numerous non-uniformly distributed pores,fractures,and other complex structures,which exhibit significant differences in hydraulic conductivity characteristics,leading to extreme complexity in the seepage process of fractured rocks.Focusing on fractured sandstone as the research object,this study first employs nuclear magnetic resonance imaging technology to obtain detailed images of the internal microstructure.Subsequently,based on image digitization techniques,the main fractures,secondary fractures,and rock matrix are precisely segmented and extracted.By constructing a numerical rock model that can accurately reflect the complex fracture(pore)structure and heterogeneous hydraulic characteristics,a comprehensive numerical simulation of the entire seepage process in fractured rocks under different seepage conditions and fracture properties is conducted.The results indicate that the seepage velocity and outlet flow rate of fractured sandstone increase with the increase in seepage pressure,fracture aperture,and fracture number,while they decrease with the increase in fracture roughness and intersection angle.The permeability coefficient obtained from the simulation analysis is highly consistent with the experimental results and exhibits similar trends.The permeability coefficient of fractured rocks is positively correlated with the fracture aperture and fracture number,while negatively correlated with the fracture roughness and intersection angle.The fractured sandstone model based on nuclear magnetic resonance imaging digitization technology can effectively characterize the complex seepage evolution characteristics of rocks,providing a feasible method for analyzing the seepage process in fractured rocks.The research findings provide powerful analytical·91·tools and theoretical guidance for the analysis and control of seepage in rock mass engineering.
作者
孙勇成
赵振兴
田益琳
卢槐
翁磊
SUN Yongcheng;ZHAO Zhenxing;TIAN Yilin;LU Huai;WENG Lei(HBIS Group Luanxian Sijiaying Iron Mine Co.,Ltd.,Tangshan 063701,China;China Merchants Real Estate(Wuhan)Co.,Ltd.,Wuhan 430035,China;School of Civil Engineering,Wuhan University,Wuhan 430072,China)
出处
《金属矿山》
北大核心
2026年第1期91-100,共10页
Metal Mine
基金
国家自然科学基金项目(编号:52278412)
湖北省自然科学基金项目(编号:2024AFB752)。
关键词
核磁共振成像
裂隙砂岩
渗流速度
数值模拟
nuclear magnetic resonance imaging
fractured sandstone
seepage velocity
numerical simulation
