In this article, the Fredericton approach to deformation analysis is presented. It is possible to use several deformation models to determine the differences between the geodetic observations or ...between the coordinates of points in geodetic network in more epochs. The most appropriate deformation model has been chosen based on statistical testing and available information about dynamics at the area of interest. First, a theoretical background of the approach is described. Then it is applied to the generated observations in two epochs. In the present example, the results of the Fredericton approach differ only slightly from the results obtained with the Delft Karlsruhe in Hannover approaches.
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The Delft approach, a method for the deformation analysis, is presented in this article. Based on geodetic measurements, the statistical significance of displacements at the surface is determined ...with statistical methods. A numerical example shows the effectiveness of the presented method.
At each point of the geodetic network kinematic quantities are considered: normal strain, shear strain and rotation. This differs from the treatment of deformations on the basis of point movements as ...the traditional geodetic approach. Strain and rotation depend on the changes of geodetic datum. In the case of two different coordinate systems in each epoch, we cannot ca/cu/ate the real value of movements, strains and rotations. Despite the empirical studies of the datum invariance, we derived analytical mathematical expressions of functional dependency of strains and rotations from the relative change of datum parameters between two measurement epochs. Practical demonstration of functional dependencies has been shown in the case of the selected planar geodetic network.
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V prispevku so obravnavane aktivnosti geodezije za potrebe določitve premikov zemeljske skorje, lokalnih premikov zemeljske površine ter premikov in deformacij grajenih objektov. Določitev premikov v ...terestrični horizontalni mreži, terestrični višinski mreži in mrežiGNSS obravnavamo na dveh stopnjah natančnosti. Dejavnosti geodezije v geotehniki so razložene v besedilu prispevka in nazorno prikazane v preglednici. Pričujoči prispevek je skupaj s prispevkom Geodezija vgeotehniki, objavljenim v Geodetskem vestniku 54(1), zaokrožena celota. ; This paper deals with surveying activities in order to define the displacement of the Earth’s crust, local displacements of the Earth’s surface, and the displacement and deformation of constructed buildings. The determinations of horizontal movements in the terrestrial network, in the terrestrial altitude network and in the GNSS network are dealt with at two levels of accuracy. Geotechnical surveying activities are explained in the paper and demonstrated in the table. The paper Geodesy in geotechnics, publishedin Geodetski vestnik 54(1), and this paper present an integral whole.
The basic problem in deformation analysis is detection and determination of stability or displacement of the points in the geodetic network during two epochs. The applicability of the methods of ...deformation analysis (Hannover, Karlsruhe) and of the simple procedure for testing point displacement was tested on practicalexamples of geodetic networks for displacement and deformation detection. The procedure, results and assessments of the testing are described.
Karlsruhe approach, which is one of the methods for the deformation analysis, is presented in the article. Based on geodetic observations, statistical significance of displacements at the surface is ...determined by statistical methods. A numerical example shows the effectiveness of the presented method.
The article describes the procedure for testing the statistical significance of point displacements in the geodetic network as the intermediate stage between the adjustment of respective epoch ...measurements and an in-depth deformation analysis. For the test statistics, a cumulative distribution function presenting the relation between the displacement and the displacement accuracy is determined by simulations. On the basis of the cumulative distribution function a critical value of the test statistic for a selected level of significance is determined. The null hypothesis presupposes that the point is not moved, it is composed. A comparison of the critical value to the test statistic value is made and the actual risk level for rejecting the null hypothesis is estimated. Further on, a practical example of implementing the test in a simulated network is given. The test statistics proved to be simple and applicable, owing to the fact that the points with significance displacements were singled out successfully.
U radu su opisani postupci deformacijske analize, koji na osnovi geodetskih mjerenja i uz pomoć statističkih metoda određuju prostorne pomake promatranog objekta. Za testiranje je uzeta simulirana ...geodetska mreža i na njoj su primijenjeni hannoverski, Ašaninov i Mihailovićev postupak. Prikazani su rezultati primijenjenih postupaka deformacijske analize i usporedbe uspješnosti određivanja stabilnih točaka.
