Diploma project is aimed to load force vector decomposition to x, y and z direction for complicated Skoda car parts. The methodology of decomposition is based on measuring of car parts deformation by strain gauges and mathematical identifation of force compoments by neural network (ANN). ANN will be trained by results of FE model simulations or by calibration on real car parts.

The Master‘s thesis is focused on measuring of the stress in the spiral case of water turbine using the strain gauges measurement. It contains the theoretical and the practical part. The theoretical part includes a description of theoretical background (basic mechanics, measurement and evaluation, strain gauges, pressure measurement, uncertainty of measurement). One of the chapters describes Water Power Plant Lipno nad Vltavou (history of power plant, issues and the history of measurement). The practical part contains a theoretical calculation of measurement uncertainty and measuring of stress on spiral case Francis turbine at Water Power Plant Lipno I (Unit TG2). Measurement was made before and after overhaul. There are described technical data of spiral cases, description of measurement, results of measuring of strain and stress including comparison with the pressure in spiral case and calculation of uncertainties of measurement.

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The process for assessing the condition of a composite bridge via strain measurements is detailed in this thesis. Field measurements were utilized to conduct the assessment of a bridge located in the northern region of Sweden. The bridge is constructed with a trough and two beams, and its structure is supported by two retaining walls that enclose a 21.8-meter-long compartment. A one hundred and sixty kilo Newton vehicle cargo of trains passes the bridge. The objective is to measure and assess the bridge in the event that the axial load increases to 300 kN. Testing commenced in February of 2023. The measurement of strain was conducted using test cases. To determine the bridge's behaviour, modelling was conducted in accordance with the measurements. For this thesis, a set of models with finite elements was established and analysed. Models are made using data taken in the field and the properties of the materials. With these models as guides, he was able to make a model that is 97% accurate of how the bridge really is. The retaining walls were left out of the models because measurements showed that they were very rigid.  The influence line was also created to find the positions of the axial loads, resulting in the largest value of bending moment. After that, those positions were used for a new model with 350 KN of axial loads. Next, the stresses resulting from the actual axial loads are computed and validated using Eurocode criteria. The last step was to compare the results of the calculation with the results of the finite element analysis. The modelling results showed values that were similar to the test results, so these were used to compare the results. The modelling results serve by measuring strain interactions d as an evaluation of the bridge's condition. The assessment shows that the bridge is stronger than when standard methods are used. / Detta examenarbete beskriver i detalj hur töjningsmätningar används för att bedöma en kompositbros tillstånd. En bro i den norra regionen av Sverige bedömdes med hjälp av fältmätningar. Bron är konstruerad med ett tråg och två balkar. Två stödmurar omsluter utrymmet på 21,8 meter. En godsvagn som väger 160 kN går över bron. Målet är att mäta och utvärdera bron i händelse av att den axiella belastningen stiger till 300 kN.  Testningen började i februari 2023. Det användes testfall för att mäta töjning. Modellering utfördes i enlighet med mätningarna för att avgöra brons beteende. En uppsättning modeller med ändliga element konstruerades och analyserades för denna avhandling. Data från fältet och materialegenskaper användes för att skapa modellerna. En modell som är 97 % korrekt av brons verkliga form kan skapas med hjälp av dessa modeller som vägledning. Modellerna inkluderade inte stödmurarna eftersom mätningar visade att de var extremt styva. Det största böjningsmomentet uppnåddes genom att använda inflytelselinjen för att hitta axiella belastningspositioner. En ny studie använde dessa positioner för 350 kN axiella belastningar. Nästa steg var att beräkna och verifiera spänningarna från de verkliga axiella belastningarna med hjälp av Eurocode-standarderna.  Det sista steget var att göra en jämförelse mellan resultaten från den ändliga elementanalysen och beräkningen. Värden som visades i modellresultaten var liknande de värden som visades i testet, så dessa användes för att jämföra resultaten. Modelleringsresultaten använder töjningsinteraktioner för att bedöma brotillståndet. Undersökningen visar att bron är starkare än med standardmetoder.