In the case of the monitoring of bridges, the determination of vertical displacements is one of the most important issues. A new measuring system has been developed and implemented for assessment of railway bridges based on measurements of the structural response to passing trains. The system uses inertial sensors: Inclinometers and accelerometers that do not need any referential points. The system records signals related to the passage of a train over a monitored bridge. The signals from inclinometers before the train’s entry are used to determine the static movement. Integrated signals from inclinometers and accelerometers are used to determine dynamic displacements when the train goes through the bridge. Signals from inclinometers are used to determine the so-called “quasi-static” component of the displacement and signal from the accelerometer to determine the dynamic component. Field tests have been carried out on a viaduct along a high-speed railway line. Periodic comparative measurements are carried out using a Total Station to verify static measurements and using inductive sensors to verify dynamic measurements. Tests of the system carried out so far have proven its usefulness for monitoring bridges in a high-speed railway (up to 200 km/h) with high accuracy while determining dynamic displacements.
8 July 2022 in Geomatics and Environmental Engineering
The design and installation of solar panels on the roofs of urban buildings often require consideration of the specific spatial conditions that affect their efficiency. The primary purpose of this work is to develop a procedure for designing and optimizing photovoltaic installations using geomatics methods and specific tools of GIS and CAD systems. The roof of the historic building A2, which is a part of the Poznań University of Technology campus, was selected as the tested object. Solar radiation modelling and determination of suitability zones were performed using SEBE (Solar Energy on Building Envelopes) in QGIS. Possible options for the placement of photovoltaic modules on the roof were simulated with CAD technique in the web-based HelioScope software. The results of the simulation show that the current roof area can generate electrical power of 99.9 MWh/year. The proposed methodology is universal for photovoltaic installations on built-up roofs and can be applied to other buildings and, consequently, the results obtained can be used to improve the content of the solar data urban geoportal.
Renewable energy from solar power plants is becoming more and more popular due to the depletion of raw materials and reduction of dependence on oil and gas and is also harmless to the natural environment. The management and rational use of land resources is currently a pressing problem in the world, including in Ukraine. One of the solutions is the development of technologies for the use of these areas and the establishment of environmentally friendly technologies for reducing air pollution, namely electricity facilities – solar power plants based on the use of photovoltaic panels. Choosing the right location for obtaining solar energy depends on many factors and constraints. Optimal location of solar farms is important to maximize the beneficial features of projects while minimizing the negative. A method of finding places in the vicinity of large cities that could be suitable for installing power plants was developed. The proposed method uses an analytical hierarchical process, analytical network process, Boolean logic and weighted linear combination. It has been implemented in the QGIS program. The method was successfully used for the city of Zaporizhia, but it can be directly implemented in any other region. That is why the presented works constitute a scheme that can be easily used to estimate large areas in order to optimally choose a place for a solar park in the vicinity of large cities. Such a model can be very useful for investors to find potential locations for solar energy before conducting detailed field research.
The subject of this study was the complex structure of a wooden historic church, which consisted of several segments that differed in the material used, the structural system employed, and the degree of wear of the elements. Particularly examined were the multi-branched columns located at the junction of different segments. The main objective of the analyses was to determine the degree of bonding of the column branches and the effect of this bonding on the operation of the entire structure. To evaluate the degree of bonding of the column branches, it was proposed to use experimental modal analysis. Based on the results of the experiment, it was found that the column branches are connected, but their cooperation is limited. Several computational models of the analyzed structure were also created, differing, for example, in the degree of bonding of the column branches. The effect of bonding the column branches on the values of stresses in the nave columns and on the values of extreme wind-induced displacements was studied.
To support the conservation efforts regarding a wooden church in Domachowo, extensive research and design work was required to strengthen its weakened structure. A variety of data and analyses are necessary to make an accurate assessment, including obtaining a dimensional model, monitoring the behavior of the structure and its response to external forces, and also performing strength analyses and verifying them with measurement data. For accurate geometric evaluation, static and dynamic measurements were required. A mathematical model and a flowchart of the necessary tasks were developed, along with the selection and installation of measuring devices. For this particular structure, static measurements were made using an automatic total station, and dynamic measurements using tilt sensors. The purpose of the analysis was to correlate the inertia measurements with the absolute tachymetric observations related to reference points fixed outside the object in order to accurately assess the behavior of the object. Another important issue was to model the column element under study in such a way that its horizontal displacements could be determined from the measured inclinations. The obtained results indicated the need to strengthen the joints of the two main parts of the structure in order to minimize the impact of dynamic weather conditions. The paper describes the measurement process, the method of calculating displacements, and the correlation of both types of data. Selected results confirming the conclusions are also presented.