Automatic characterization of rock mass discontinuities using 3D point clouds

Structure from Motion (SfM) is a powerful tool to provide 3D point clouds from a sequence of images taken from different remote sensing technologies. The use of this approach for processing images captured from both Remotely Piloted Aerial Vehicles (RPAS), historical aerial photograms, and smartphones, constitutes a valuable solution for the identification and characterization of active landslides. We applied SfM to process all the acquired and available images for the study of the Champlas du Col landslide, a complex slope instability reactivated in spring 2018 in the Piemonte Region (north-western Italy). This last reactivation of the slide, principally due to snow melting at the end of the winter season, interrupted the main road used to reach Sestriere, one of the most famous ski resorts in north-western Italy. We tested how SfM can be applied to process high-resolution multisource datasets by processing: (i) historical aerial photograms collected from five diverse regional flights, (ii) RGB and multi-spectral images acquired by two RPAS, taken in different moments, and (iii) terrestrial sequences of the most representative kinematic elements due to the evolution of the landslide. In addition, we obtained an overall framework of the historical development of the area of interest, and distinguished several generations of landslides. Moreover, an in-depth geomorphological characterization of the Champlas du Col landslide reactivation was done, by testing a cost-effective and rapid methodology based on SfM principles, which is easily repeatable to characterize and investigate active landslides.

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Special Issue on “Terrestrial Laser Scanning”: Editors’ Notes

Sensors ◽

10.3390/s19204569 ◽

2019 ◽

Vol 19 (20) ◽

pp. 4569

Author(s):

Joan R. Rosell-Polo ◽

Eduard Gregorio ◽

Jordi Llorens

Keyword(s):

Point Cloud ◽

Laser Scanning ◽

Terrestrial Laser Scanning ◽

Point Clouds ◽

Special Issue ◽

Alternative Technologies ◽

Cloud Processing ◽

3D Point Clouds ◽

Point Cloud Processing

In this editorial, we provide an overview of the content of the special issue on “Terrestrial Laser Scanning”. The aim of this Special Issue is to bring together innovative developments and applications of terrestrial laser scanning (TLS), understood in a broad sense. Thus, although most contributions mainly involve the use of laser-based systems, other alternative technologies that also allow for obtaining 3D point clouds for the measurement and the 3D characterization of terrestrial targets, such as photogrammetry, are also considered. The 15 published contributions are mainly focused on the applications of TLS to the following three topics: TLS performance and point cloud processing, applications to civil engineering, and applications to plant characterization.

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Surface Subsidence Prognosis above an Underground Longwall Excavation and Based on 3D Point Cloud Analysis

Minerals ◽

10.3390/min10010082 ◽

2020 ◽

Vol 10 (1) ◽

pp. 82 ◽

Cited By ~ 3

Author(s):

Andrej Pal ◽

Janez Rošer ◽

Milivoj Vulić

Keyword(s):

Rock Mass ◽

Longwall Mining ◽

Underground Mining ◽

Point Clouds ◽

Surface Subsidence ◽

Protection Measures ◽

Engineering Research ◽

3D Point Clouds ◽

Research Activities ◽

And Control

Impacts of underground mining have been reduced by continuous environmental endeavors, scientific, and engineering research activities, whose main object is the behavior and control of the undermined rock mass and the subsequent surface subsidence. In the presented Velenje case of underground sublevel longwall mining where coal is being exploited both horizontal and vertical, backfilling processes and accompanying fracturing in the coal layer, and rock mass are causing uncontrolled subsidence of the surface above. 3D point clouds of the study were acquired in ten epochs and at excavation heights on the front were measured at the same epochs. By establishing a sectors layout in the observational area, smaller point clouds were obtained, to which planes were fitted and centroids of these planes then calculated. Centroid heights were analyzed with the FNSE model to estimate the time of consolidation and modified according to excavation parameters to determine total subsidence after a certain period. Proposed prognosis approaches for estimating consolidation of active subsidence and long term surface environmental protection measures have been proposed and presented. The C2C analysis of distances between acquired 3D point clouds was used for identification of surface subsidence, reclamation areas and sink holes, and for validation of feasibility and effectiveness of the proposed prognosis.

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A sensor skid for precise 3D modeling of production lines

ISPRS Annals of Photogrammetry Remote Sensing and Spatial Information Sciences ◽

10.5194/isprsannals-ii-5-117-2014 ◽

2014 ◽

Vol II-5 ◽

pp. 117-122 ◽

Cited By ~ 3

Author(s):

J. Elseberg ◽

D. Borrmann ◽

J. Schauer ◽

A. Nüchter ◽

D. Koriath ◽

...

Keyword(s):

3D Modeling ◽

Production Line ◽

Laser Scanning ◽

Terrestrial Laser Scanning ◽

Point Clouds ◽

Production Lines ◽

3D Point Clouds ◽

Laser Scanners ◽

Rapid Characterization

Motivated by the increasing need of rapid characterization of environments in 3D, we designed and built a sensor skid that automates the work of an operator of terrestrial laser scanners. The system combines terrestrial laser scanning with kinematic laser scanning and uses a novel semi-rigid SLAMmethod. It enables us to digitize factory environments without the need to stop production. The acquired 3D point clouds are precise and suitable to detect objects that collide with items moved along the production line.

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Using open-source software for extracting geomechanical parameters of a rock mass from 3D point clouds: Discontinuity set extractor and SMRTool

Rock Mechanics and Rock Engineering: From the Past to the Future ◽

10.1201/9781315388502-190 ◽

2016 ◽

Cited By ~ 3

Author(s):

A Riquelme ◽

R Tomás ◽

M Cano ◽

A Abellán

Keyword(s):

Rock Mass ◽

Open Source ◽

Open Source Software ◽

Point Clouds ◽

3D Point Clouds ◽

Geomechanical Parameters

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A new approach for semi-automatic rock mass joints recognition from 3D point clouds

Computers & Geosciences ◽

10.1016/j.cageo.2014.03.014 ◽

2014 ◽

Vol 68 ◽

pp. 38-52 ◽

Cited By ~ 102

Author(s):

Adrián J. Riquelme ◽

A. Abellán ◽

R. Tomás ◽

M. Jaboyedoff

Keyword(s):

Rock Mass ◽

Point Clouds ◽

New Approach ◽

3D Point Clouds

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A New Method for Automatic Extraction and Analysis of Discontinuities Based on TIN on Rock Mass Surfaces

Remote Sensing ◽

10.3390/rs13152894 ◽

2021 ◽

Vol 13 (15) ◽

pp. 2894

Author(s):

Xiang Wu ◽

Fengyan Wang ◽

Mingchang Wang ◽

Xuqing Zhang ◽

Qing Wang ◽

...

Keyword(s):

Rock Mass ◽

Clustering Algorithm ◽

Point Clouds ◽

New Method ◽

Rock Masses ◽

Average Deviation ◽

Density Peaks ◽

3D Point Clouds ◽

Discontinuity Sets ◽

Dip Angle

Light detection and ranging (LiDAR) can quickly and accurately obtain 3D point clouds on the surface of rock masses, and on the basis of this, discontinuity information can be extracted automatically. This paper proposes a new method to automatically extract discontinuity information from 3D point clouds on the surface of rock masses. This method first applies the improved K-means algorithm based on the clustering algorithm by fast search and find of density peaks (DPCA) and the silhouette coefficient in the cluster validity index to identify the discontinuity sets of rock masses, and then uses the hierarchical density-based spatial clustering of applications with noise (HDBSCAN) algorithm to segment the discontinuity sets and to extract each discontinuity from a discontinuity set. Finally, the random sampling consistency (RANSAC) method is used to fit the discontinuities and to calculate their parameters. The 3D point clouds of the typical rock slope in the Rockbench repository is used to extract the discontinuity orientations using the new method, and these are compared with the results obtained from the classical approach and the previous automatic methods. The results show that, compared to the results obtained by Riquelme et al. in 2014, the average deviation of the dip direction and dip angle is reduced by 26% and 8%, respectively; compared to the results obtained by Chen et al. in 2016, the average deviation of the dip direction and dip angle is reduced by 39% and 40%, respectively. The method is also applied to an artificial quarry slope, and the average deviation of the dip direction and dip angle is 5.3° and 4.8°, respectively, as compared to the manual method. Furthermore, the related parameters are analyzed. The study shows that the new method is reliable, has a higher precision when identifying rock mass discontinuities, and can be applied to practical engineering.

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