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1

Modernising the control network for determining displacements in hydraulic structures using automatic measurement techniques

Zaczek-Peplinska Janina, Saloni Lech

Journal of Water and Land Development

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2023

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no. 59

66--75

EN

Over the last two decades, geodetic surveying has seen significant advancements with terrestrial and unmanned aerial vehicle (UAV) laser scanning, alongside automatic observations being increasingly utilised throughout the construction process. In the context of dam structures, periodic geodetic displacement measurements are a compulsory component of control measurements and safety assessments. In Poland, however, control measurements have largely remained rooted in traditional techniques such as classic linear and angular measurements and precise levelling. These methods are typically carried out within distinct control networks, i.e. without dual-function observation points and targets. Furthermore, network points (pillars, targets) have often not been renewed since their installation several decades ago, and glass discs, used for crown measurements in the baseline method, frequently face damage. Changes in property ownership and modifications in environmental regulations are compounded by these issues, which often impede the proper upkeep of the sight line. The article proposes the adaptation and reconstruction of control networks to incorporate automatic observation techniques, including linear and angular measurements. This approach includes activities aimed at reconstructing and supplementing damaged network structures, modernising the geodetic process of determining structure displacements, and enhancing the accuracy, credibility, and reliability of geodetic displacement measurement results. The article presents the findings of an inventory assessment conducted on the existing control network infrastructure, focusing on the analysis of displacements for structures with diverse constructions and functions - a concrete dam (class I) and a water damming weir with a water intake. Furthermore, it presents practical conclusions regarding the efficient organisation of geodetic control measurements.

2

Pod kontrolą tachimetru

Grudziński Michał, Karsznia Krzysztof

Geodeta : magazyn geoinformacyjny

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2021

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nr 7

26--30

3

Concrete surface evaluation based on the reflected TLS laser beam’s intensity image classification

Zaczek-Peplinska J., Osińska-Skotak K.

Studia Geotechnica et Mechanica

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2018

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Vol. 40, nr 1

56--64

EN

Dynamically developing terrestrial laser scanning technology (TLS) provides modern surveying tools, that is, scanning total stations and laser scanners. Owing to these instruments, periodic control surveys of concrete dams were performed as a part of geodetic monitoring yield point models characterised by quasicontinuity. Using the results of such measurements as a base, one can carry out a number of geometric analyses as well as acquire information for detailed analytical and calculative considerations. The scanner, similar to total station, by determining distances and angles, identifies spatial coordinates (X, Y, Z) of the surveyed points. Registration of the reflected laser beam’s intensity value (Intensity) emitted by the scanner provides additional information on the surveyed object. Owing to high working speed and the large amount of the collected data, the scanners became an indispensable tool for geodesists. The article assesses the possibility of application of terrestrial laser scanning in surveying changes in the surface of a concrete dam based on the experimental measurements. The condition of the dam’s downstream concrete wall was evaluated. The evaluation included changes in the surface’s roughness, cracks, seepage points, erosion caused by plant overgrowth and the degressive durability parameter of the used material (concrete). The article presents an example of the application of the results of a laser scan in the assessment of the condition of a water dam’s external concrete surfaces. The results of experimental measurements were analysed – the results of a scan of the downstream concrete wall of a dam in Ecker (Germany) using two laser scanners characterised by different technical parameters, that is, laser wavelength (laser’s colour), range, definable point density, method of distance measurement – Leica C10, Z+F Imager 5006h. The measurement was carried out in the same weather conditions from the same sites of the test base. The results of the measurements were analysed using, inter alia, statistical methods by defining template fields and supervised and unsupervised classification methods in reference to the selected fragments of the Surface characterised by known concrete surface properties. Various classification algorithms were used. The obtained results make it possible to assess the suitability of the proposed methodology of evaluating the concreto surface’s condition and establish tool selection principles to match the practical application requirements.

4

Terrestrial laser scanning in monitoring of anthropogenic objects

Zaczek-Peplinska J., Kowalska M.

Geodesy and Cartography

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2017

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Vol. 66, no. 2

347--364

EN

The registered xyz coordinates in the form of a point cloud captured by terrestrial laser scanner and the intensity values (I) assigned to them make it possible to perform geometric and spectral analyses. Comparison of point clouds registered in different time periods requires conversion of the data to a common coordinate system and proper data selection is necessary. Factors like point distribution dependant on the distance between the scanner and the surveyed surface, angle of incidence, tasked scan’s density and intensity value have to be taken into consideration. A prerequisite for running a correct analysis of the obtained point clouds registered during periodic measurements using a laser scanner is the ability to determine the quality and accuracy of the analysed data. The article presents a concept of spectral data adjustment based on geometric analysis of a surface as well as examples of geometric analyses integrating geometric and physical data in one cloud of points: cloud point coordinates, recorded intensity values, and thermal images of an object. The experiments described here show multiple possibilities of usage of terrestrial laser scanning data and display the necessity of using multi-aspect and multi-source analyses in anthropogenic object monitoring. The article presents examples of multisource data analyses with regard to Intensity value correction due to the beam’s incidence angle. The measurements were performed using a Leica Nova MS50 scanning total station, Z+F Imager 5010 scanner and the integrated Z+F T-Cam thermal camera.

5

Determination of horizontal geodetic control networks for engineering objects using optoelectronic techniques

Ćmielewski K., Kuchmister J., Gołuch P., Wilczyńska I., Kowalski K.

Reports on Geodesy and Geoinformatics

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2015

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Vol. 98

39--51

EN

The correctness of the geodetic service of an engineering object not seldom requires designing, alignment or renewing of geodetic situational control points. Building robots often cause that fixed situational control points are partly or completely inaccessible. For setting the position of these control points, there is worked out the methodology using the optoelectronic method. The prepared set of tools realizes the method’s assumptions and enables to determine the sides and control points based on the set of laser planes. In this article there is presented the innovative set of geodetic equipment for fixing horizontal control points. The presented set has been experimentally tested under laboratory conditions taking its functionality, operation range and applied accuracy into account. The measurement accuracy of the set of tools, resulting from identification of the energetic centres of laser planes’ edges, visualizing the sides of geodetic control networks, is within the range of ±0.02mm - ±0.05mm. There were also discussed exemplary versions of shapes and structures of horizontal geodetic control networks (regular and irregular), which are possible to be fixed with the use of the constructed set of tools.

6

Directions of the proposed changes in the technical standards in the field of engineering geodesy

Parzyński Z.

Reports on Geodesy

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2011

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z. 1/90

369--376

EN

The INSPIRE Directive and its implementation in Poland in the form of the Act on Spatial Information Infrastructure enforce the adjustment of Polish law to the new requirements. In the Head Office of Geodesy and Cartography work that exceeds changes adjusting technical standards to the requirements related to INSPIRE is currently ongoing. In the article the changes of a general nature that concern all or almost all of the instructions and guidelines which are in force will be discussed. Moreover, the author will refer in more detail to the directions of the proposed changes relating to the engineering geodesy.

7

Methods of movement disruptions compensation of sounding vessel

Makar A.

Reports on Geodesy

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2004

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nr 1/68

27--34

EN

As a result of influence of exterior factors, such as the wind, the current, wavy motion and changing the speed and location of the load on the sounding vessel, its movement is disrupted. Influence of these disruptions increases for smaller sounding vessels. In this paper methods of stabilization of sounding vessel's movement and compensation of influence of movement disruptions on accuracy of hydrographic soundings have been shown.

8

Cuboid fitting into a set of points

Cellmer S.

Technical Sciences / University of Warmia and Mazury in Olsztyn

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2003

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nr 6

141-148

EN

A method of vertical cuboid fitting into a set of points is described in the paper. This method was employed to determine the layout corrections during the construction of a swimming pool.

PL

Opisano sposób wpasowania pionowego prostopadłościanu w układ punktów o znanych współrzędnych przestrzennych. Sposób ten zastosowano do wyznaczenia poprawek trasowania przy budowie basenu sportowego.

9

Koncepcja numerycznego modelu geometrii torów w procesie napraw nawierzchni

Dobrowolski B.

Prace Instytutu Geodezji i Kartografii

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2002

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T. 49, z. 105

77--95

PL

Artykuł omawia zagadnienia wymogów dokładnościowych wyznaczania geometrycznej osi torów przeznaczonych dla dużych szybkości pociągów. Zawiera także charakterystyką Kolejowej Osnowy Specjalnej i pomiarów osi torów w nawiązaniu do osnowy odpowiedniej do tych wymagań. Na koniec przedstawiona jest w zarysie koncepcja numerycznego modelu geometrii torów.

EN

Author discusses in the article problem of geodetic service in the course of repairs of tracks used for fast trains. In order to understand better criteria of accuracy requirements, conceming determination of axes of tracks, and in conseąuence selection of geodetic methods fulfilling these reąuirements, author presents briefly basie definitions characterizing geometrical axis of track. In particular definition of curvature of geometrical track axis is important, as well as method of its measurement and related problems of long-wave deformations. Advantages and disadvantages of algorithms of programs applied for regulation of track axis, which use involute and geodetic coordinate systems, were discussed. Criterion of continuity of curvature is the most important for measurement accuracy of track axis. Joint application of this criterion with requirement of elimination of long-wave deformations of geometrical track axis creates strict accuracy conditions for measurements. These reąuirements are met by the Special Railway Control Network and hence by measurements of track axes attached to this network, discussed in this article. Furthermore, the problem is concentrated on geodetic service of track devices used for moving and lifting tracks, which also must meet high accuracy reąuirements. For these works "total station" or GPS receiver can be used. Author created the concept of digital model of track geometry, which includes sets of points of track axis and gauge of constructions extracted from digital railway map. Each repair would update the model and in conseąuence digital map. Fuli benefits from implementing the concept would be visible after improvement of height measurements with the use of GPS system.

10

Problemy geodezyjnej kontroli bezpieczeństwa budynków znajdujących się w strefie wpływu głębokich wykopów

Janusz J., Janusz W.

Prace Instytutu Geodezji i Kartografii

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1998

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T. 45, z. 96

47--72

PL

Omówiono technologię budowy ścian szczelinowych umożliwiających wykonywanie głębokich wykopów w bezpośrednim sąsiedztwie płytko posadowionych budynków. Omówiono technologię pomiarów osiadań i pionowych deformacji fundamentów budynków p o d wpływem wykonywania w sąsiedztwie głębokich wykopów. Zilustrowano na przykładzie zależność między osiadaniami i pionowymi deformacjami fundamentów budynków a pracami ziemnymi i budowlanymi w sąsiadującym z nimi głębokim wykopie.

EN

Technology o f building slotted walls, used for protection during deep earthworks, is outlined in the article. The authors presented technology o f geodetic control measurements, used for determining: 1) vertical displacements o f benchmarks placed on the carrying walls o f the existing buildings, which are located close to the construction area o f the underground garages or buildings with several underground storeys; 2) horizontal displacements o f points placed on the slotted walls due to allevation, caused by deepening o f excavation surrounded by these walls. The problems related to the range o f control measurements, location o f observation stands, reference and checked points, were discussed in the article. The authors presented the example illustrating relations between the determined displacements of benchmarks, vertical displacements and changes o f inclinations o f foundations o f the existing buildings and particular phases o f earthworks and construction works in the deep excavation located close to these buildings. In was emphasized, that deformations o f foundations o f the existing buildings can appear not only due to deepening o f excavation, but also earlier as a result o f construction and bolting o f slotted wall in close neighbourhood o f these buildings.