Application of a new in situ 3D laser scanner to study the scale effect on the rock joint surface roughness

2004 ◽  
Vol 41 (2) ◽  
pp. 329-335 ◽  
Author(s):  
N. Fardin ◽  
Q. Feng ◽  
O. Stephansson
Keyword(s):  
Surface Roughness ◽  
Scale Effect ◽  
Rock Joint ◽  
Laser Scanner ◽  
Joint Surface

scholarly journals Neutrosophic Function with NNs for Analyzing and Expressing Anisotropy Characteristic and Scale Effect of Joint Surface Roughness

2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Rui Yong ◽  
Leiyu Gu ◽  
Jun Ye ◽  
Shi-Gui Du ◽  
Man Huang ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Scale Effect ◽  
Large Scale ◽  
Rock Joint ◽  
Rock Joints ◽  
Joint Surface ◽  
Roughness Coefficient ◽  
Statistical Assessment ◽  
Natural Rock

The shear behavior of rock mass significantly depends upon the surface roughness of rock joints which is generally characterized by the anisotropy characteristic and the scale effect. The large-scale natural rock joint surfaces, at Qingshi Town, southeast of Changshan County, Zhejiang Province, China, were used as a case study to analyze the roughness characteristics. A statistical assessment of joint roughness coefficient (JRC) indicated the roughness anisotropy of different sized rock joints. The lower limit (JRCmean-σ) was regarded as the determinate information, and the difference between lower and upper limits represented indeterminate information. The neutrosophic number (NN) was calculated to express the various JRC values. The parametric equations for JRC anisotropic ellipse were presented based on the JRC statistical assessment of joint profiles of various orientations. The JRC values of different sized joint samples were then quantitatively described by the neutrosophic function. Finally, a neutrosophic parameter ψ for evaluating the scale effect on the surface roughness anisotropy was introduced using the ratio of maximum directional roughness to minimum directional roughness. The case study indicates that the proposed method has the superiority in moving forward from subjective assessment to quantitative and objective analysis on anisotropy characteristic and scale effect of joint surface roughness.

scholarly journals Neutrosophic Function for Assessing the Scale Effect of the Rock Joint Surface Roughness

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Rui Yong ◽  
Shaonan Tan ◽  
Jun Ye ◽  
Shigui Du
Keyword(s):  
Surface Roughness ◽  
Scale Effect ◽  
Rock Joint ◽  
Small Samples ◽  
Joint Surface ◽  
Roughness Coefficient ◽  
Joint Roughness ◽  
Large Joint ◽  
Negative Effect ◽  
Jrc Value

A new investigation method is proposed for recording large-sized joint profiles and making statistical analyses of the joint roughness coefficient (JRC) values of the 10–300 cm sized profiles. The mechanical hand profilograph is used for joint roughness measurement due to its advantage of easy operation and high accuracy in recording joint traces. Based on the proposed method, it provides sufficient samples from various positions on the large joint profile, which allows the statistical evaluation of JRC values. A neutrosophic number (NN) is employed for revealing determinate and/or indeterminate information as it consists of determinate and indeterminate parts. Due to the uncertainty of JRC in the real world, NN is chosen to represent the JRC value, which is not only random but also a fuzzy indefinite parameter. The neutrosophic function is used to analyze and express the scale effect of joint surface roughness, and its derivative is used to describe the changing trend of the scale effect. The results show that the JRC value of the joint profile is related to the scale and has a negative effect on the surface roughness of the rock joint. The indeterminate information about the scale effect on joint roughness is described by the neutrosophic functions, and the derivative indicated that the JRC values of small samples are more sensitive than those of large-sized examples. When the length of the sample exceeds the stationarity limit of 80 cm, the roughness appears to be almost scale independent.

scholarly journals Scale Dependence of Waviness and Unevenness of Natural Rock Joints through Fractal Analysis

Geofluids ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-18
Author(s):  
Yingchun Li ◽  
Shengyue Sun ◽  
Hongwei Yang
Keyword(s):  
Surface Roughness ◽  
Rock Joint ◽  
Fractal Dimensions ◽  
Window Size ◽  
Scale Dependence ◽  
Rock Joints ◽  
Joint Surface ◽  
Triangular Prism ◽  
Natural Rock ◽  
Waviness And Unevenness

The scale dependence of surface roughness is critical in characterising the hydromechanical properties of field-scale rock joints but is still not well understood, particularly when different orders of roughness are considered. We experimentally reveal the scale dependence of two-order roughness, i.e., waviness and unevenness through fractal parameters using the triangular prism surface area method (TPM). The surfaces of three natural joints of granite with the same dimension of 1000 mm×1000 mm are digitised using a 3D laser scanner at three different measurement resolutions. Waviness and unevenness are quantitatively separated by considering the area variation of joint surface as grid size changes. The corresponding fractal dimensions of waviness and unevenness in sampling window sizes ranging from 100 mm×100 mm to 1000 mm×1000 mm at an interval of 100 mm×100 mm are determined. We find that both the fractal dimensions of waviness and unevenness vary as the window size increases. No obvious stationarity threshold has been found for the three rock joint samples, indicating the surface roughness of natural rock joints should be quantified at the scale of the rock mass in the field.

Quantitative Parameters for Rock Joint Surface Roughness

2000 ◽  
Vol 33 (4) ◽  
pp. 217-242 ◽  
Author(s):  
T. Belem ◽  
F. Homand-Etienne ◽  
M. Souley
Keyword(s):  
Surface Roughness ◽  
Rock Joint ◽  
Joint Surface ◽  
Quantitative Parameters

scholarly journals Experimental Study on Relationship Between Mechanical, Seepage Characteristics and 3D Morphology Parameters of Marble Joint

2016 ◽  
Vol 10 (1) ◽  
pp. 513-523 ◽  
Author(s):  
Chenlin Wang ◽  
Baohua Guo ◽  
Long Wang
Keyword(s):  
Normal Stress ◽  
Linear Relation ◽  
Rock Joint ◽  
Laser Scanner ◽  
Coarse Grained ◽  
Joint Surface ◽  
3D Morphology ◽  
Hydraulic Aperture ◽  
Seepage Characteristics ◽  
Morphology Parameters

In order to investigate the influence of 3D morphology parameters of marble joint surface on its mechanical and seepage characteristics, artificial joints of coarse-grained marbles were scanned by Tianyuan OKIO-typed 3D laser scanner; and then, the professional software was used to obtain the 3D morphology parameters of marble joint surface. Tests of water flowing through a single joint were conducted under different normal stress and feeding water head by using self-developed radial flowing system, and the exponential function between flow rate per head and normal stress, the linear relation between equivalent hydraulic aperture and mechanical aperture, and the linear relation between joint closure and normal stress were obtained. The relationships between regression parameters in above three formulas and 3D morphology parameters of joint surface were also studied by fitting method. All in all, the results may provide a reference to understand the mechanical and seepage characteristics of rough rock joint.

scholarly journals Evaluation of Rock Joint Surface Roughness by Using Fractal Model.

1997 ◽  
Vol 113 (7) ◽  
pp. 555-560 ◽  
Author(s):  
Sumihiko MURATA ◽  
Toshiaki SAITO
Keyword(s):  
Surface Roughness ◽  
Rock Joint ◽  
Fractal Model ◽  
Joint Surface

scholarly journals Stress effect & scale effect on shear properties of double saw-tooth rock joint surface

2021 ◽  
Vol 31 (1) ◽  
pp. 39-49
Author(s):  
Zhanyou Luo ◽  
Mingyao Jiang ◽  
Linfei Mo ◽  
Baoping Zou ◽  
Man Huang
Keyword(s):  
Shear Strength ◽  
Normal Stress ◽  
Scale Effect ◽  
Rock Joint ◽  
Joint Surface ◽  
Joint Control ◽  
Stress Effect ◽  
Peak Shear Strength ◽  
Shear Properties ◽  
Tooth Width

Abstract The shear properties of rock joint control the stability of rock and have an important impact on natural disasters such as landslides and debris flow. In order to study the stress effect and scale effect of shear properties of double saw-tooth rock joint, cement mortar is selected as similar material, a series of mix ratio tests are carried out, and the best mix ratio is obtained. Using rock joint integrated mold and joint panel produced by 3D printing technology, several groups of double saw-tooth joint specimens with different saw-tooth heights, saw-tooth widths, and saw-tooth spacings are made. Under multiple levels of normal stress, direct shear tests of different scale specimens are carried out by self-developed multifunctional rock-soil contact damage test system. Results show that the shear failure modes of double saw-tooth rock joint include couple effect of overriding and cutting off, and cutting off effect, which are mainly controlled by the rock joint morphology and normal stress. Peak shear strength increases with the increase of saw-tooth width and spacing, but the change with saw-tooth height is not obvious. Peak shear strength and peak friction angle of the double saw-tooth rock joint have significant characteristics of stress effect and scale effect.

scholarly journals Effect of small-scale snow surface roughness on snow albedo and reflectance

2020 ◽  
Author(s):  
Terhikki Manninen ◽  
Kati Anttila ◽  
Emmihenna Jääskeläinen ◽  
Aku Riihelä ◽  
Jouni Peltoniemi ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Laser Scanner ◽  
Small Scale ◽  
Snow Surface ◽  
Roughness Effects ◽  
Bidirectional Reflectance Factor ◽  
Reflectance Factor ◽  
Bulk Volume ◽  
The Impact

Abstract. The primary goal of this paper is to present a model of snow surface albedo accounting for small-scale surface roughness effects. The model is based on photon recollision probability and it can be combined with existing bulk volume albedo models, such as TARTES. The model is fed with in situ measurements of surface roughness from plate profile and laser scanner data, and it is evaluated by comparing the computed albedos with observations. It provides closer results to empirical values than volume scattering based albedo simulations alone. The impact of surface roughness on albedo increases with the progress of the melting season and is larger for larger solar zenith angles. In absolute terms, surface roughness can decrease the total albedo by up to about 0.1. As regards the bidirectional reflectance factor (BRF), it is found that surface roughness increases backward scattering especially for large solar zenith angle values.

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