Today high-rise timber buildings are more popular than ever and designers all over the world have discovered the beneficial material properties of timber. In the middle of the 1990’s cross-laminated timber (CLT), was developed in Austria. CLT consists of laminated timber panels that are glued together to form a strong and flexible timber element. In recent years CLT has been on the rise and today it is regarded as a good alternative to concrete and steel in the design of particularly tall buildings. Compared to concrete and steel, timber has lower mass and stiffness. A high-rise building made out of timber is therefore more sensitive to vibration. The vibration of the building can cause the occupants discomfort and it is thus important to thoroughly analyze the building’s dynamic response to external excitation. The standard ISO 10137 provides guidelines for the assesment of habitability of buildings with respect to wind-induced vibration. The comfort criteria herein is based on the first natural frequency and the acceleration of the building, along with human perception of vibration. The aim of this thesis is to identify the important structural properties affecting a dynamic analysis of a high-rise timber building. An important consequence of this study is hopefully a better understanding of the interactions between the structural properties in question. To investigate these properties and any potential interactions a so-called factorial experiment is performed. A factorial experiment is an experiment where all factors are varied together, instead of one at a time, which makes it possible to study the effects of the factors as well as any interactions between these. The factors are varied between two levels, that is, a low level and a high level. The design of a factorial experiment includes all combinations of the levels of the factors. The experiment is performed using the software FEM-Design, which is a modeling software for finite element analysis. A fictitious building is modelled using CLT as the structural system. The modeling and the subsequent dynamic analysis is repeated according to the design of the factorial experiment. The experiment is further analyzed using statistical methods and validated according to ISO 10137 in order to study performance and patterns between the different models. The statistical analysis of the experiment shows that the height of the building, the thickness of the walls and the addition of mass are important in a dynamic analysis. It also shows that interaction is present between the height of the building and the thickness of the walls as well as between the height of the building and the addition of mass. Most of the models of the building does not satisfy the comfort criteria according to ISO 10137. However, it still shows patterns that provides useful information about the dynamic properties of the building. Lastly, based on the natural frequency of the building this study recognizes the stiffness as more relevant than the mass for a building with CLT as the structural system and with up to 16 floors in height. / Idag är höga trähus mer populära än någonsin och konstruktörer runtom i världen har upptäckt de fördelaktiga materialegenskaperna hos trä. I mitten på 1990-talet utvecklades korslimmat trä (KL-trä) i Österrike. KL-trä består av hyvlade brädor som limmas ihop för att bilda en lätt och stark träskiva. På senare år har KL-trä varit på uppgång och idag anses materialet vara ett bra alternativ till betong och stål i framför allt höga byggnader. Jämfört med betong och stål har trä både lägre massa och styvhet. En hög träbyggnad är därför mer känslig för vibrationer. En vibrerande byggnad kan leda till obehag för de boende och det är därför viktigt att analysera byggnadens dynamiska respons då den utsätts för yttre belastning. Standarden ISO 10137 ger riktlinjer för att kunna utvärdera komfortkravet för byggnader med avseende på människors känslighet för vibrationer orsakade av vind. Komfortkravet i fråga jämför byggnadens första naturliga egenfrekvens med dess acceleration. Syftet med detta examensarbete är att identifiera de viktiga egenskaperna i en dynamisk analys av en hög träbyggnad. Förhoppningsvis leder det här examensarbetet till en ökad förståelse av samspelseffekterna mellan dessa egenskaper. För att undersöka dessa egenskaper och eventuella samspelseffekter genomförs ett så kallat faktorförsök. Ett faktorförsök är ett försök där alla faktorer varieras tillsammans, istället för en och en, vilket gör det möjligt att studera effekterna av faktorerna samt eventuella samspelseffekter. Faktorerna varieras mellan två nivåer: en låg nivå och en hög nivå. Ett faktorförsök använder sig av samtliga kombinationer av faktorernas nivåer. Försöket utförs med hjälp av programmet FEM-Design, vilket är ett modelleringsverktyg för FE-analys. En fiktiv byggnad modelleras med CLT som stomsystem och en dynamisk analys görs. Försöket analyseras ytterligare med hjälp av statistiska metoder och valideras enligt ISO 10137. Dessa steg upprepas enligt faktorförsöket. Den statistiska analysen av försöket visar att höjden på byggnaden, tjockleken på väggarna samt en ökad massa är viktiga i en dynamisk analys. Den visar också på en samspelseffekt mellan höjden på byggnaden och tjockleken på väggarna, samt mellan höjden på byggnaden och en ökad massa. Merparten av modellerna av byggnaden uppfyller inte komfortkravet enligt ISO 10137. Däremot går det att urskönja mönster som bidrar med viktig information om byggnadens dynamiska egenskaper. Avslutningsvis, baserat på byggnadens naturliga egenfrekvens framhåller den här studien byggnadens styvhet framför dess massa då byggnaden i fråga stabiliseras med KL-trä och har upp till 16 våningar.

Damping and natural frequency of a vibrating body or a system is not easy to estimate during the design phase of~project. If the body is submerged in water, estimating becomes even more complicated. This~work focuses on experimental determination of the liquid influence on an oscillating body. The~presented modal analysis was executed on two bodies when being surrounded by air, but~also when gradually and fully submerged in water using two reservoirs with different dimensions. The collected data was analyzed with a suggested hybrid method, which determined the damping ratio and the natural frequency. Added mass was calculated employing the Ansys software. Part of the presented work focuses on the selection of a suitable time window for the Fourier transform.

Immersion of the body into the fluid creates additional effects which must be considered when designing the machines. Additional effects from the fluid influence the dynamic properties of the body. In this work the decrease of the natural frequency and the increase of the damping ratio during the gradual immersion of the body into the fluid are investigated. Diploma thesis is based on an experiment, which is performed on a series of flat strip steel components of various widths. The first three bending and first three torsion shapes of the free-hanging body are examined. Emphasis is placed on the influence of part width. In the next phase of the experiment, the influence of the proximity of the solid wall to the dynamic properties of the cantilever beam is examined. Further, the determination of the added density from the fluid is performed by modal analysis using the ANSYS software.

The master thesis deals with design of the fully differential frequency filters working in the current mode and is focused on possibilities of the natural frequency and the quality factor adjustment. At the beginning, there is a brief description of frequency filters and active elements (MO-CF, FD-CF and DACA), which are used in the thesis. Furthermore, simplified signal flow graphs design method and transformation of passive and active elements to the differential structures are described. The designs of four differential circuitries which provide possibility of tuning the natural frequency or quality factor by the gain of the DACA element are shown in the thesis. Simulation results made in OrCAD program with help of third-order models are included. The practical implementation of the differential frequency filter for tuning of the natural frequency by the DACA elements is shown in the last chapter.

This thesis deals with the design and assessment of footbridge for pedestrians and cyclists in the city of Hranice, Rybare district. The footbridge will serve as a crossing point over the river Bečva and will conect cycling trail with the street Rybarska. The content of this paper is to propose two different variants of structures. One of these options is selected based on their economic evaluation and further processed. Length of the bridge is 50m.

This Master’s thesis deals with analysis of mechanical behaviour of the synchronous generator and assessment of the possibility of reducing the mass of the frame of the generator. The aims of this work were: to perform the stress-strain analysis and modal analysis of the required model of the synchronous generator, to assessment influence of single part of the frame of the generator over its stiffness and design construction modification of the frame of the generator, which reduce its mass.

The thesis deals with flexible shaft couplings especially with new category of flexible couplings on the principle of fluid. Mathematical model of gas spring and rotor system with two degrees of freedom are derivated in this work. Last part of the work deals with design modification of flexible coupling with gas springs.

The subject of the diploma thesis is design and structural analysis of loadbearing steel structure of observation tower, which is located southeast of Černá Hora, township Blansko. The design is processed in two options. Parts of the thesis are engineering report, structural design report for both of the options and graphical documentation in specified range. The structure’s height is 25.3 m and maximal ground plan dimension is 6 x 6 m. Steel grade S355 was chosen as main material. The sub-objectives of the structural analysis are load effects calculations (permanent load, imposed load and climatic load), entering of loads to the calculation model and calculation of internal forces and deformations. An assessment of the supporting elements and selected joints is also included. There are dynamic design features considered in the calculation. All calculations were performed in accordance with valid ČSN EN standards.

This Master’s thesis deals with the computational modeling of complex natural frequencies of the tram wheels during cornering. The aim of this work is to determine eigenvalues, perform analysis of the influence of different parameters on eigenvalues and perform harmonic response analysis in order to find surface velocities that can be used in future noise emission analysis.

This thesis is concerned with vibration analysis of the roots blower chassis. In the beginning it describes methods of solution in low frequency region. Next part is about finite element model of the chassis and computing natural frequencies, eigen modes and vibration spreading and analysis possible construction changes which should lead to lower vibrations.