摘要
甘肃北山为高放废物深地质处置库场址的主预选区。针对场址区花岗岩受剪切破坏形成裂隙的渗流特性进行研究,具有重要的工程建设指导意义。为探究北山花岗岩多尺度粗糙裂隙几何特征对非线性渗流场演化的影响规律,对剪切条件下花岗岩裂隙断面的几何特征及渗流特性进行了分形建模研究。结果表明,粗糙裂隙的粗糙程度和开度在模型尺度变化过程中存在完全的自相似性,二者的分布特征在分布空间尺度变化过程中始终保持一致;渗流速度场、梯度场及散度场只存在局部特征的延续,尤其是不同尺度下对应的数量场均服从于正态分布;随着观察尺度的增大场内空间起伏逐渐减小,三场内的尖锐突变逐渐消失且向平滑过渡,这意味着观察尺度越大,粗糙裂隙渗流被误判为平行板渗流的概率越大,即粗糙断面渗流特性的精准描述依赖于几何尺度。
The Beishan area in Gansu province is the main pre-selected site for deep geological disposal of high-level radioactive waste,it therefore bears implications for the study of fracture seepage characteristics of granite caused by shear failure.This paper investigated the fractal modeling of the geometric and seepage characteristics of granite fracture sections under shear conditions,with the aim to explore the effect of the geometric characteristics of multi-scale rough fractures on the evolution of nonlinear seepage field in Beishan granite.Results show that the roughness height and aperture of rough fractures have complete self-similarity in the process of model scale change,whose distribution are always consistent in the process of spatial scale change.The seepage velocity field,gradient field and divergence field only demonstrate the continuation of local characteristics,in particular,the corresponding quantity fields at different scales are subject to normal distribution.As the observation scale increases,the spatial fluctuation in the field gradually decreases,the sharp mutations in the three fields gradually disappear and are smoothed.This indicates that the larger the observation scale,the greater the probability that the seepage of rough fracture is misjudged as the seepage of parallel plate,therefore the seepage characteristics of rough section would be more accurately described by taking the geometric scale into account.
作者
薛东杰
侯孟冬
程建超
贾震
刘殷彤
辛翠
徐颜卓
王路军
Xue Dongjie;Hou Mengdong;Cheng Jianchao;Jia Zhen;Liu Yintong;Xin Cui;Xu Yanzhuo;Wang Lujun(School of Mechanics and Civil Engineering,China University of Mining and Technology-Beijing,Beijing 100083,China;State Key Laboratory of Water Resource Protection and Utilization in Coal Mining,National Institute of Low Carbon and Clean Energy,Beijing 102211,China)
出处
《矿业科学学报》
CSCD
2023年第5期663-676,共14页
Journal of Mining Science and Technology
基金
中央高校基本科研业务经费重点领域交叉创新项目(JCCXLJ01)
国家能源集团2030重大项目先导项目(GJNY2030XDXM-19-01.2)
煤炭开采水资源保护与利用国家重点实验室开放基金(GJNY-20-113-04)。
关键词
剪切破坏
粗糙断面
粗糙度
多尺度
分形渗流模型
orthogonal shearing
rough section
roughness
multiscale
fractal seepage model
