• Explosives and Blasting
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• v.22 no.3
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• pp.103-111
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• 2004

The existing methods that can be adopted for measuring joints involve either to use borehole or photogrammetry. Due to restricted space, acquisition of data in limited area, and measurement errors, above methods have limitations acquiring the objective and correct results. To get over defects of existing joint measurement methods, joints have been measured using 3D-Laser scanner with accuracy and efficiency. This research aims to investigate an accuracy and applicabiliy of 3D-Laser scanner for measuring rock slope joints. Measurement of rock slope joints has been executed using 3D-Laser scanner & clinometer and then, results from both methods are compared. Results from both methods indicate that they show nearly equal features for joint distributions and numbers of joint information obtained by 3D-Laser scanner are much more than ones measured using clinomer. Therefore, 3D-Laser scanner turns out to be very effective by the fact that it contributes to reduce investigation costs & periods, objectify data from rock slope joints.

• The Journal of Engineering Geology
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• v.16 no.4 s.50
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• pp.337-349
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• 2006

Seven hundred and fifty one fractures of the rhyolitic tuffaceous rock masses were mapped using 6 scanlines placed on rock slope exposures that were within 8.02 km of Busan-Ulsan highway. These data were analyzed to find the number of fracture sets that exist in the rock slopes and the probability distributions of orientation, spacing, trace length and fracture size in 3-D for each of the fracture sets. All the fracture set orientation distributions exhibit high variability. The Fisher distributions were found to be unsuitable to represent the statistical distribution of orientation for most of the fracture sets. The probability distributions, gamma, exponential and lognormal were found to be highly suitable to represent the distribution of spacing and semi-trace length of fracture sets. In obtain-ing these distributions, corrections were applied for sampling biases associated with spacing and trace length. The generated fracture system in 3-D was used to make predictions of fracture traces for each fracture set on 2-D win-dows. Developed stochastic 3-D fracture network for the rock mass was validated by comparing statistical proper-ties of the observed fracture traces on scanlines with the predicted fracture traces on the scanlines. This exercise fumed out to be successful.

• Tunnel and Underground Space
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• v.25 no.1
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• pp.97-106
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• 2015

We must precisely investigate the mechanical characters of rock to design rock slope safely and efficiently. But the method of clinometer has some disadvantages. So, we need a new measurement that can replace the method of clinometer. In this study, we analyze the reliability of joint orientation measurements in rock slope using the 3D laser scanner and program Split-FX that is a point cloud data analysis software. We could acquire the 495 pieces joint data through the automatic extraction of features. And we confirmed that there were some errors occurred with ${\pm}4^{\circ}$ of dip and ${\pm}5^{\circ}$ of dip direction. Generally, the method of clinometer has ${\pm}5^{\circ}$ and ${\pm}10^{\circ}$ error ranges of the joint orientation(dip/dip direction) that are the results of the advance research. Therefore, we analyzed the method of 3D laser scanner, and it is found to be efficient, reliable. This method is expected to mend the disadvantages of Clinometer method.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.4
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• pp.91-99
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• 2018

Mechanical Properties of Rock Slope as a safe and effective interpretation should be thoroughly investigated. Clinometer, however, this new measurement due to the restrictions of the research for the joint orientation is needed. In this study, characteristics of the joint orientation can be used to analyze the joint orientation of developing a joint survey system that can be applied to the field. The system is developed and Analysis software to hardware. Hardware is composed to measure the joint orientation of measuring module, measuring the transfer of data transfer module. From the software is measuring module from the data to analyze the orientation of the joint development, and drone joint orientation survey system named. Can not be measured by the investigation, including regional development approach is a system that has been difficult if the Field Application of the lab test results of the joint orientation and effectively.

• Tunnel and Underground Space
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• v.22 no.6
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• pp.393-402
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• 2012

A behavior of ridge-cut rock slope had been monitored by installing inclinometers and regional slope movement toward rear side of cut face was detected. To delineate the governing factors of slope behavior, especially backward slip of ridge-cut slope, petrographic characteristics of rock cores obtained from four drilled boreholes had been examined. BIPS images inside boreholes had been acquired and structural characteristics of slope rock had been studied. Mechanical properties of discontinuity planes distributed in the drilled core had been measured and the shear strength of coal seam imbedded-discontinuity planes also had been obtained by performing the direct shear test. Monitoring results of slope behavior had been analyzed by comprehensibly considering both the mechanical and structural characteristics of slope rock and coal seam-imbedded discontinuity planes, and the potential governance of coal seam and clay minerals embedded in the joint plane on the regional slope behavior has been also identified.

• The Journal of Engineering Geology
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• v.34 no.2
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• pp.317-327
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• 2024

When a non-persistent joint system is formed in a large-scale rock slope, slope failure may occur due to presence of a the stepped sliding surface. Such a surface can be divided into joint-to-joint sliding surfaces or joint-to-rock bridge sliding surfaces. In the latter case, the rock bridge provides shear resistance parallel to the joint and tensile resistance perpendicular to the joint. The load of the sliding rock can lead to failure of the rock bridge, thereby connecting the two joints at each ends of the bridge and resulting in step-path failure of the slope. If each rock bridge on a slope has the same length, the tensile strength is lower than the shear strength, resulting in the rock bridges oriented perpendicular to the joint being more prone to failure. In addition, the smaller the ratio of discontinuity spacing to length, the greater the likelihood of step-path failure. To assess the risk of stepped sliding on a rock slope with non-persistent joints, stability analysis can be performed using limit equilibrium analysis or numerical analysis. This involves constructing a step-path failure surface through a systematic discontinuity survey and analysis.

• Tunnel and Underground Space
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• v.19 no.1
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• pp.1-10
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• 2009

Site characterization for structural stability in rock masses mainly involves the collection of joint property data, and in the current practice, much of this data is collected by hand directly at exposed slopes and outcrops. There are many issues with the collection of this data in the field, including issues of safety, slope access, field time, lack of data quantity, reusability of data and human bias. It is shown that information on joint orientation, spacing and roughness in rock masses, can be automatically extracted from LIDAR (light detection and ranging) point floods using the currently available Split-FX point cloud processing software, thereby reducing processing time, safety and human bias issues.

• Journal of the Korean Geotechnical Society
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• v.23 no.6
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• pp.97-102
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• 2007

Though the stability analysis of soil slopes widely employs the limit equilibrium method, the study on the jointed rock slopes must consider the direction of joint and the characteristics of Joint at the same time. This study analyzes the result of the change in the factors which show the characteristics of discontinuity and the shape factor of rock slopes, and so on, in an attempt to validate the propriety as to the interpretation of jointed rock slope stability which uses the general finite element program. First, the difference depending on the flow rules was compared, and the factor effect study was conducted. The selected independent variables included the direction of joint which displays the mechanical characteristics of discontinuity, adhesive cohesion, friction angle, the inclination and height of rock slope which reveal the shape of slope and surcharge load. And the horizontal displacement was numerically interpreted at the 1/3 point below the slope, a dependent variable, to compare the relative degree of factor effects. The findings of study on factor effects led to the validation that the result of horizontal displacement for each factor satisfied various engineering characteristics, making it possible to be applied to stability interpretation of jointed rock slope. A modelling is possible, which considers the application of the result of real geotechnical surveys & laboratory studies and the non-linear characteristics when designing the rock slope. In addition, the stress change which may result from the natural disaster, such as precipitation, and the construction, can be expressed. Furthermore, as the complicated rock condition and the ground supporting effect can be considered through FEM, it is considered to be very useful in making an engineering decision on the cut-slope, reinforcement and so on.

• Tunnel and Underground Space
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• v.28 no.3
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• pp.193-208
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• 2018

In order to interpret rock slope safely and effectively, the mechanical properties of the rock must be carefully investigated. However, due to the limitations of clinometer usage, a new measure of measurement is required to complement these limitations. In this study, a measuring device was developed to analyze the characteristics of joint orientation, and to apply the orientation of joint to the field. The developed measuring equipment is divided into analysis software and hardware. The hardware was composed of a measuring module that measures the joint orientation of rock and a transport module that transmits the measurement data. The software was developed to analyze the orientation of the joint from the data obtained from the measuring module and is named Drone Joint Orientation Survey Measurement. The developed measuring equipment was well field capable if it could not be measured by the inspector, such as in areas where access was difficult, and was capable of effectively analyzing the lab test results for the orientation of the joint.

• Proceedings of the Korean Society for Rock Mechanics Conference
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• 1995.03a
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• pp.109-120
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• 1995

절리가 발달된 경암질 암반내에서 터널을 굴착할 때에 발생하는 심각한 문제중의 하나는 암반내에 존재하는 불연속면과 굴착에 의하여 형성되는 자유면에 의하여 생성된 블록의 낙반 사고이다. R.E. Goodman, Gen-hua shi$^{3)}$ 등에 의하여 제안된 블록이론은 암반사면이나 지하공동에 존재하는 절리들의 방향성을 조사하여 우세한 방향의 절리들에 의하여 발생하는 블록들의 안정, 불안정 및 낙반의 가능성 여부를 판정할 수 있도록 하였다. (중략)