Ústav geodézie

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Long-term deformation measurements of atypical roof timber structures
(FCE CTU Prague, 2014-12-01) Bureš, Jiří; Švábenský, Otakar; Kalina, Marek
The paper includes conclusions from evaluation of results obtained from long-term measuring of innovative atypical roof timber structures. Based on the results of measurements of vertical and horizontal deformation components it is possible to analyze the real behaviour of structures in given conditions. By assessing deformations in various stages, including particularly external and internal environment temperatures, relative air humidity and moisture content of wood, decisive parameters for real structure behaviour can be established. The data are processed from period 2001 – 2013.
New velocity analysis in geodynamic network Sněžník based on GNSS measurement reproces- sing using reprocessed IGS products
(IRSM AS CR, 2014-03-21) Puchrik, Lukáš; Švábenský, Otakar; Pospíšil, Lubomil; Weigel, Josef
The availability of IGS reprocessed products enabled comprehensive reprocessing of all GNSS data from the Local Geodynamic SNĚŽNÍK network over period 1997-2011. All calculations were performed using the Bernese GPS Software 5.0. The absolute method of Precise Point Positioning (PPP) was used for the first time within the network providing interesting results. Tha main evaluation of recent movement tendencies was done using the common relative method where the nearest IGS stations were used as reference.
Problems of Creation and Usage of 3D Model of Structures and Theirs Possible Solution
(MDPI, 2020-01-20) Bartoněk, Dalibor; Buday, Michal
This article describes problems that occur when creating three-dimensional (3D) building models. The first problem is geometric accuracy; the next is the quality of visualization of the resulting model. The main cause of this situation is that current Computer-Aided Design (CAD) software does not have sufficient means to precision mapping the measured data of a given object in field. Therefore the process of 3D model creation is mainly a relatively high proportion of manual work when connecting individual points, approximating curves and surfaces, or laying textures on surfaces. In some cases, it is necessary to generalize the model in the CAD system, which degrades the accuracy and quality of field data. The article analyzes these problems and then recommends several variants for their solution. There are described two basic methods: using topological codes in the list of coordinates points and creating new special CAD features while using Python scripts. These problems are demonstrated on examples of 3D models in practice. These are mainly historical buildings in different locations and different designs (brick or wooden structures). These are four sacral buildings in the Czech Republic (CR): the church of saints Johns of Brno-Bystrc, the Church of St. Paraskiva in Blansko, further the Strejc’s Church in Židlochovice, and Church of St. Peter in Alcantara in Karviná city. All of the buildings were geodetically surveyed by terrestrial method while using total station. The 3D model was created in both cases in the program AUTOCAD v. 18 and MicroStation.
Recent Reactivation of Variscan Tectonic Zones: A Case of RodlKapliceBlanice Fault System (Bohemian Massif, Austria/Czech Republic)
(Springer Nature, 2024-02-22) Roštínský, Pavel; Pospíšil, Lubomil; Švábenský, Otakar; Melnyk, Anastasiia; Nováková, Eva
The Rodl-Kaplice-Blanice fault system (RKB) of Variscan shear origin, repeatedly active since the Late Paleozoic to the Recent, is expressed by a number of lithological contacts, distinct geophysical gradients and many landforms. A general trend of the RKB as well as linear configuration of its internal architecture is fairly similar to those of topical near Rhine Graben and Alpine-Carpathian transition area as the two other consistent recently reactivated large-scale tectonic structures in the extended (thinned) crust of central Europe. In middle part of the RKB, the occurring linear topographic and geological features parallel to the main RKB sections point to the existence of a wide tectonic zone in the crust following the fault system. Our multidisciplinary study includes a summary of corresponding basic geological data, overview of seismic, regional geophysical and geomorphological conditions, primary model of recent kinematic activity in the RKB area derived from the space (Global Navigation Satellite System-GNSS) monitoring and terrestrial (repeated high precision levelling) geodetic data and comparison of these various information. The obtained knowledge indicates that the RKB is active up to similar to 1.0 mm horizontally and > 0.5 mm vertically. The fault system area in the Bohemian Massif can be subdivided into the three parts of diverse tectonic structure and block kinematics. Sinistral horizontal movements are highest near the southern surface sections (Rodl-Kaplice, Rudolfov and Drahotesice faults), whereas noticeable vertical differentiation is going on mainly along the Blanice and Kourim faults in the north where the RKB activity is gradually decreasing towards the extensive Elbe shear zone with transverse movements. The middle part of the RKB is dislocated by a large active transverse tectonic structure of the South Bohemian Basins (SBB) with variable horizontal velocity vectors of surface GNSS stations. Most of the weak regional earthquakes have been recorded west of the RKB. Besides faults of the SBB, these were mainly associated with the RKB-subparallel Lhenice fault. Based on the earthquake distribution and foci depths, the latter fault can have similar structural position as the RKB related to lower part of the Variscan level in the similar to 10-12 km depth.
Case Study of Remodelling the as-Built Documentation of a Railway Construction into the BIM and GIS Environment
(MDPI, 2023-05-30) Bartoněk, Dalibor; Bureš, Jiří; Vystavěl, Ondřej; Havlíček, Radomír
Building Information Modelling (BIM) is a modern approach to managing the process of prepa-ration, realization and operation of building objects including their documentation throughout their life cycle, based on database agenda platform. The aim of our research is to analyze and innovate existing engineering procedures with the aim: 1. to remodel the existing CAD docu-mentation into BIM for the purpose of public procurement, 2. to provide guaranteed data to the IS of the Digital Map of Public Administration and 3. to provide data for the design of new rail-way structures or their reconstruction. The aim of the case study was to evaluate the effective-ness of remodelling the existing as-built documentation of a railway construction into a com-mon BIM data environment (CDE), in which further subsequent construction agenda should be managed for the remaining period of its life cycle. Using the documentation for construction re-alization of the railway station Šumice, this 3D documentation was remodeled into the BIM data environment CDE and alternatively also into the 2D GIS environment. The BIM data standard developed by the State Fund for Transport Infrastructure was analyzed during the documenta-tion reworking. An important parameter of the documentation rework was the use of a geodetic reference system fully compatible with the cadastral system in the Czech Republic. It turned out that the general data standard is only partially applicable for railway structures containing many special objects and many objects requiring individual classification. The remodelling of existing graphical data proved faster and more efficient in a GIS environment (layer oriented) compared to the need for 3D remodelling in a BIM CDE (object oriented). Experimental results have demonstrated the effectiveness of remodelling underground technical infrastructure ob-jects, while the visible surface situation is often more effectively captured by current progressive bulk data acquisition technologies. In a CDE environment, existing as-built documentation data can be efficiently stored and administered and progressively, for the procurement and execution of construction, purposefully remodeled only to the extent required in BIM or converted into an exchangeable Digital Technical Map (DTM) format for public administration.

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