上下节理面的初始接触状态对节理后续的剪切和剪切渗流特性起到了重要作用。自行研制的TJXW-3D型便携式岩石节理表面形貌测量仪具有识别标志点的功能,利用该表面形貌测量仪首先对侧面贴有标志点的处于初始闭合状态的节理试样和上下节理面分别进行扫描,扫描结束后利用标志点将上下节理面分别对齐到其在初始接触状态下的坐标系中,最终获得节理初始空腔数据。初步分析了3种不同粗糙度的节理面在初始接触状态下节理隙宽的分布规律,与前人研究成果基本吻合。各节理隙宽分布符合高斯分布,平均隙宽为0.31~0.41 mm。为了展示节理空腔的应用,将计算得到的节理初始空腔数据应用到节理法向闭合Brown模型中,与法向压缩试验结果进行对比。Brown模型预测结果比试验结果相对较大,主要原因在于Brown模型无法考虑各突起之间的相互作用。研究成果可为节理剪切-渗流的研究,尤其是为节理剪切渗流的数值研究奠定了模型基础。
Abstract
The initial contact of the two surfaces of a joint has important effect on its shear and coupled shear-flow properties. TJXW-3D portable rock surface topography scanner developed by Tongji University is able to realize special reference points. In this article, the scanner was first used to digitize joints in initial closed state and joint with two surfaces, respectively. With permanent reference points attached to the sides of the joint samples, the subsequent measurements were automatically transferred into the coordinate system of the first measurement, thus the void space of the joint in initial contact can be obtained. The aperture distributions of void spaces of three joints with different surface roughness under initial contact state were analyzed, and the results were in accordance with prior studies. The aperture of joints ranged from 0.31 mm to 0.41 mm, following Gaussian distribution. Furthermore, the Brown joint closure model was used to demonstrate the application of the void space calculation method, and the result was compared with that of normal compression test. The Brown model result was larger than test result as Brown model does not consider the interaction between upheaves. The result lays a foundation for the numerical research on the coupled shear-flow property of joint.
关键词
节理 /
空腔 /
初始接触状态 /
隙宽分布 /
Brown模型
Key words
joint /
void space /
initial contact state /
aperture distribution /
Brown model
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基金
国家自然科学基金项目(41327001,41472248)
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