Digital Photogrammetric Technique Research Articles

Measurement of displacement for open pit to underground mining transition using digital photogrammetry

The newest digital photogrammetric technology is applied to investigate the deformation characteristics of rock mass when it changes from open pit to underground mining. First, the calculation formulas of pixel deformation and instrumental error were derived. Based on this, the calculation of digital camera calibration were obtained and used to calibrate the physical model for rock mass undergoing the changing mining process. Finally, the deformation characteristics of rock mass were revealed based on a geotechnical engineering of Daye iron mine and the monitored results of digital photogrammetry were compared with the dial indicators. It was found that the surface deformations measured by digital photogrammetric technique are similar to the results using dial indicators. The maximum error between these two was less than 0.02mm. These tests demonstrate the efficacy of digital photogrammetry as a powerful technique for deformation measurement in the geotechnical model tests.

Shoreline Change Monitoring using High Resolution Digital Photogrammetric Technique

ABSTRACT Ahn, Y.; Shin, B., and Kim, K.-H., 2017. Shoreline change monitoring using high resolution digital photogrammetric technique. In: Lee, J.L.; Griffiths, T.; Lotan, A.; Suh, K.-S., and Lee, J. (eds.), The 2nd International Water Safety Symposium. Journal of Coastal Research, Special Issue No. 79, pp. 204–208. Coconut Creek (Florida), ISSN 0749-0208. Shoreline change has been measured with conventional surveying techniques such as Total station, GNSS, EDM etc. These measurements provide short/long term variation of nearshore evolution which enables us to estimate erosional and accretion sediment volume of the beach. This observation of ocean morphology currently has been utilized through the advance of optical imaging system and related digital image analysis. When deployed with proper viewing geometry, ground based digital imaging system can provide higher spatial/temporal resolution of shoreline change than satellite remote sensing data. In this study, we focus on generating time series of shore l...

Displacement measurement techniques and numerical verification in 3D geomechanical model tests of an underground cavern group

In this paper, the stability of an underground cavern group is investigated on the basis of large-scale 3D geomechanical model tests and numerical simulations. Multiple measurement techniques are developed to measure the convergence of deformation in the cavern, displacements at key points in the side walls and the damage pattern during the excavation simulation process. The digital photogrammetric technique and fiber Bragg grating (FBG) based displacement sensing bars are applied to measure displacements in the surrounding rock masses. Mini multi-point extensometers with high-precision grating scales are developed as transducers for displacement monitoring. Afterward, a nodal-based Discontinuous Deformation Analysis (NDDA) method is applied to simulate the whole process of the physical model tests and to compare with experimental results. The variation process and law curves of the displacements in the surrounding rock and at key points in the side walls are obtained at excavation stages. The study shows that the application of the displacement measurement methods used in the surrounding rock masses for large-scale model tests of cavern group under true 3-D stress state have achieved satisfactory results.

Three-dimensional topography of fracture surfaces obtained by a digital photogrammetric technique

Fractures parallel to rift, grain and hardway planes of Inada granite were produced by a uni-axial tensile test. The obtained surface topography was analyzed by digital stereo-photogrammetry. A pair of photograph was taken by a digital camera with a macro lens mounted on a copy stand system. The measurement accuracy is about 0.02 mm parallel to the fracture surface, and 0.1 mm in the vertical direction, for the specimen of 30 mm diameter. From the results of calculation of roughness parameter, the fracture parallel to the rift plane is the smoothest, and the fracture parallel to the grain plane is smoother than the fracture parallel to the hardway plane. In addition, we discussed the applicability of the digital photogrammetric technique to other geo-engineering and geological objects.

Large-scale geomechanical model testing of an underground cavern group in a true three-dimensional (3-D) stress state

The stability of a large cavern group at great depth is discussed on the basis of large-scale three-dimensional (3-D) geomechanical model tests and numerical simulations. The model tests are described in detail. Improvements in the tests were made in terms of experimental techniques and advanced measurement methods. The model tests utilized active loading on six sides of a rock mass in a true 3-D stress state. During the model construction, precast blocks were fabricated and monitoring holes were defined prior to test initiation. Newly developed combination ball-sliding walls were installed on each of the major loading surfaces to reduce the friction induced by model deformation. A unique grouting and installation technique employing prestressed cables was adopted in the tests. A digital photogrammetric technique, displacement sensing bars using fiber Bragg grating (FBG) technology, and mini multipoint extensometers were developed for measuring deformation. Overloading tests were then conducted for different overburden depths, and 3-D numerical analyses were performed to simulate the testing procedures. Conclusions regarding the stability of the cavern group were developed based on a comparison between the experimental and numerical results.

多時期の空中写真から作成された数値表層モデルを用いた放牧草地における土壌侵食の地形解析

We surveyed soil erosion and slope failure in a grazed pasture in South Hokkaido using digital surface model (DSM) for geomorphic analysis, also, estimated about adaptation to a monitoring in a grazed pasture using DSM. In this study, DSMs were extracted by multi-temporal aerial photographs and digital photogrammetric technique. Digital elevation model (DEM) was extracted by contour map of paper for accuracy validation of DSM absolute accuracy. As a result of DSM accuracy evaluation on the basis of DEM, in all the ages, root mean square deviation of height direction were with satisfactory accuracy. Using extracted multi-temporal DSMs, large-scale soil erosion and slope failure were able to be performed. In addition, growths of grass were able to be grasped. However, it was difficult to extract the minute geomorphic change formed in the grazed pasture. Application of photogrammetric technique to monitoring of grazed pasture definite showed may be able to contribute to preservation of a grazed pasture, and maintenance.

多時期の空中写真から作成したＤｉｇｉｔａｌ Ｃａｎｏｐｙ Ｍｏｄｅｌによる森林キャノピーのモニタリング

Digital canopy models (DCMs) were extracted by multi-temporal aerial photographs (1964∼2004) and digital photogrammetric technique for forest canopy monitoring. In this study, ground contorol points (GCPs) were extracted by IKONOS image and digital elevation model (DEM) from LiDAR data. Bundle block adjustment with self-calibration was used for aerial triangulation, because camera callibration reports were not available. The generated DCM which was obtained in 2004 was compared with DCM from LiDAR data (obtained in 2004). Most of all pixel by aerial photographs were corresponded with DCM from LiDAR data. However, small gap areas were difficult to detect. Excluding gap areas, root mean square error of DCM from aerial photo was 3.78 meter. Using extracted multi-temporal DCMs, forest canopy changes, such as tree growth, clear-cutting and fallen damage, were figured out. Multi-temporal DCMs were found to be effective in monitoring forest canopy.

A photogrammetric technique for the analysis of palatal three-dimensional changes during rapid maxillary expansion

The aim of this study was to assess, by a digital photogrammetric technique, the relative dimensional changes before and after rapid maxillary expansion (RME). The transverse diameters and volumetric variations of the palate were measured by photogrammetry on study casts taken at three different phases of therapy: at the beginning of treatment (T1), on removal of the rapid expander, after expansion and retention for three months (T2), and six months after appliance removal (T3). The sample consisted of 30 children, (age range 7-8 years), all with a crossbite; 15 were angle Class I, six Class II and nine Class III. They were treated with an acrylic splint expander with two turns per day until the maxillary molar palatal cusps were in contact with the mandibular molar buccal cusps. The RME device was used as a passive retainer for three months, after which it was removed. During the following six months, no retention was used and no orthodontic treatment was undertaken. The findings demonstrated a significant relapse (P < 0.001) in the dental transverse diameter in all patients six months after appliance removal, although the palatal volume remained stable.

Performance prediction of TBM disc cutting on granitic rock by the linear cutting test

This paper aims to estimate the TBM disc cutter performance on Hwandeung Granite, one of the representative rock types in Korea by the Linear Cutting Machine. In the Linear Cutting test, the digital photogrammetric technique was newly adopted to measure three-dimensional cutting volumes and to apply them to the derivation of design parameters of TBM cutterhead. In this study, a series of linear cutting tests by a TBM disc cutter with the diameter of 17 inches were carried out by varying cutter spacing as well as cutter penetration conditions. From the tests, the optimum ratio of cutter spacing and penetration depth was derived for Hwandeung Granite. However, experimental results showed that three-dimensional cutting volumes measured by the photogrammetrical technique were not very close to those that were simply calculated from mechanical set-up values of each linear cutting test. Considering that the cutting procedure of a TBM disc cutter is not one-dimensional but three-dimensional failure mechanism, the use of three-dimensional cutting volumes as a performance parameter of a TBM disc cutter is indispensable to design a more accurate and reliable TBM cutterhead. (A) This paper was presented at Safety in the underground space - Proceedings of the ITA-AITES 2006 World Tunnel Congress and the 32nd ITA General Assembly, Seoul, Korea, 22-27 April 2006. For the covering abstract see ITRD E129148. Reprinted with permission from Elsevier.

Monitoring the morphological evolution of the Sciara del Fuoco during the 2002–2003 Stromboli eruption using multi-temporal photogrammetry

After a period of anomalous activity affecting the Volcano of Stromboli (Aeolian volcanic arc, Italy), the “Sciara del Fuoco” slope, situated on the north–east flank of the island, was affected by major landslides on December 30, 2002. Recent lava accumulations starting from the beginning of the eruption (December 28, 2002) and a portion of the subaerial and submarine deposits were detached. As a result, tsunami waves several meters high affected the coasts of the island. After the event, monitoring activities, coordinated by the Italian Civil Protection Department, included systematic photogrammetric surveys. The digital photogrammetric technique was adopted to extract high-resolution digital elevation models and large-scale orthophotos. The comparison between the data collected before the eruption and that acquired on January 5, 2003, together with bathymetric data, allowed to define the geometry and to estimate the volume of the surfaces involved in the landslides. The following 13 photogrammetric surveys (from January to September 2003) enabled the monitoring of the continuous and relevant morphological changes induced by both the lava flow and the evolution of the instability phenomena. The method adopted for the data analysis and the results obtained are described in the paper.

A digital photogrammetric method for measuring horizontal surficial movements on the Slumgullion earthflow, Hinsdale County, Colorado

The traditional approach to making aerial photographic measurements uses analog or analytic photogrammetric equipment. We have developed a digital method for making measurements from aerial photographs which uses geographic information system (GIS) software, and primarily DOS-based personal computers. This method, which is based on the concept that a direct visual comparison can be made between images derived from two sets of aerial photographs taken at different times, was applied to the surface of the active portion of the Slumgullion earthflow in Colorado to determine horizontal displacement vectors from the movements of visually identifiable objects, such as trees and large rocks. Using this method, more of the slide surface can be mapped in a shorter period of time than using the standard photogrammetric approach. More than 800 horizontal displacement vectors were determined on the active earthflow surface using images produced by our digital photogrammetric technique and 1985 (1:12,000-scale) and 1990 (1:6,000-scale) aerial photographs. The resulting displacement field shows, with a 2-m measurement error (~10%), that the fastest moving portion of the landslide underwent 15–29 m of horizontal displacement between 1985 and 1990.

The anisotropy of surface roughness measured using digital photogrammetric technique : M. W. Jessell, S. J. D. Cox, P. Schwarze & W. L. Power, in: Fractography: fracture topography as a tool in fracture mechanics and stress analysis, ed M.S. Ameen, (Geological Society, London; Special Publication, 92), 1995, pp 27–37

The anisotropy of surface roughness measured using digital photogrammetric technique : M. W. Jessell, S. J. D. Cox, P. Schwarze & W. L. Power, in: Fractography: fracture topography as a tool in fracture mechanics and stress analysis, ed M.S. Ameen, (Geological Society, London; Special Publication, 92), 1995, pp 27–37

The anisotropy of surface roughness measured using a digital photogrammetric technique

The anisotropy of surface roughness measured using a digital photogrammetric technique

The anisotropy of surface roughness measured using a digital photogrammetric technique

The anisotropy of surface roughness measured using a digital photogrammetric technique