|
|
Implicit and Explicit Method in nonlinear Dynamics
Vaněčková, Adéla ; Hradil, Petr (referee) ; Němec, Ivan (advisor)
The final thesis „Explicit and Implicit methods in nonlinear dynamics“ deals with the issue of geometrical and physical nonlinear analysis of structures exposed to seismic loading by the methods of direct integration of equations of motion. Solution by the explicit and the implicit method is compared for three material models. While the differences between the results of the explicit method and the implicit Newmark method are small as expected, the differences are substantial between the results of different material models. However, these differences are explained and they are in full concordance with the theoretical assumptions for the pertinent material models. The conclusion of the final thesis is check of correctness of the results of the new module of the program system RFEM for both tested numerical methods and all three analyzed material models. (linear elastic, plastic Drucker-Prager and the Mazars damage model). With sufficient precision of results, both explicit and implicit numerical methods showed to be suitable for seismic analysis. The implicit method can provide several times faster calculation than the explicit one, but the determination of the optimal time step is problematic and time consuming, so the suitability of use of both methods for seismic analysis is comparable.
|
|
|
Study of dynamic effect on a bridge structure with moving loads
Zavřelová, Michaela ; Martinásek, Josef (referee) ; Vlk, Zbyněk (advisor)
The goal of the master thesis is a dynamic parametric study on the dynamic effects of high-speed train using the HSLM-A load model on a railway bridge. The calculation model is processed, in RFEM 5.29.01 with RF-MOVE module and prerelease versions RFEM 6 and RSTAB 9, as a 2D member in the XZ plane. Furthermore, static load cases and load models LM 71 and HSLM-A are created. The HSLM-A load model is processed for universal trains A1-A10, which each cross the railway bridge at a total of 15 speeds ranging from 120 km/h to 400 km/h. A detailed parametric study of the dependence of the maximum deformation and acceleration in the Z direction on the speeds of each train set is performed. Modal and time history analysis is used in the parametric study. Part of the work is to determine the resonance region.
|
|
|
Lateral-torsional buckling of beams - analysis of specific cases
Piják, Jiří ; Barnat, Jan (referee) ; Bajer, Miroslav (advisor)
Thesis deals with flexural-lateral buckling of asymmetric cross sections, especially assessment according to ČSN EN 1993-1-1. Models are based on bar, shell and solid finite element method. Assessment of software Scia Engineer and RFEM are analysed in bar model. Plate and volume model uses shell and solid elements and initial imperfections. Computing is geometrically nonlinear. Correspondence of bar and plate model is studied. Optimal amplitude is suggested. Simple beam loaded with continuous line loading is taken as an example.
|
|
|
Dynamic analysis of lightweight bridge construction
Krzywoň, Filip ; Nevařil, Aleš (referee) ; Vlk, Zbyněk (advisor)
The thesis compares the dynamic response of lightweight footbridge structure. Two finite element models were made. One in Ansys 15.0 software, and another in RFEM 5.05 structural software. The results of the models were compared to each other. The response to dynamic excitation from pedestrians was evaluated in accordance to ČSN EN 1990/A2.
|
|
|
Static analysis of the roof
Hořínek, Josef ; Vlk, Zbyněk (referee) ; Martinásek, Josef (advisor)
The Bachelor Thesis focuses on a static analysis of a timber roof truss. This roof trust is part of the saddle roof on the family home. The load on the structure is calculated manually according to valid standards. The load is divided into a total of 11 load cases. The calculation model of the structure is created in RFEM. Results of internal forces and deformations are checked by manual calculation using methods for statically indeterminate structures. These values are compared at the end.
|
|
| |
|
|
Static analysis of suspension bridge variants
Zavřelová, Michaela ; Martinásek, Josef (referee) ; Vlk, Zbyněk (advisor)
The bachelor's thesis deals with the static analysis of individual models of suspension footbridges. A manual calculation of the cable was processed. The actual position of the cable was determined by calculation. The manual calculation was compared with the RFEM calculation program. Furthermore, the models were loaded with manually calculated loads. The bachelor's thesis deals with the influence of pylon deflection on the global deformations of cable and bridge deck during individual load cases and combinations. For one of the models, the optimization of construction was processed.
|
|
| |
|
|
Static analysis of the cylindrical tank
Frimlová, Eva ; Martinásek, Josef (referee) ; Vlk, Zbyněk (advisor)
This bachelor thesis describes structural analysis of cylindrical tank. The goal of this thesis is creating a computational algorithm in a software called MATLAB, using which the structural analysis on idealized models of cylindrical tank is solved. These models are the rod model and the model with plane elements. This bachelor thesis is divided in several parts. Firstly, there is defined the structure, material and load of cylyndrical tank. Second part is about rod model, stiffness method and the calculation using this method. Next part is about model with plane elements, finite element method and its calculation. In the last part, there are results from each part and their comparison.
|
|
|
Design of steel-concrete arch structure of footbridge over the river Svratka
Vraňanová, Veronika ; Marván, David (referee) ; Nečesal, Petr (advisor)
The main goal of this diploma thesis was to project a design of arch bridge‘s framework over the Svratka river. This single-span bridge has the span of 52,5m. The framework is constructed from a pair of beams, suspended from the pair of beams bent towards each other. The bridge deck is coupled with steel crosspieces. The construction design was executed in computing programme Dlubal RFEM 5.07. The individual components of the framework were assessed in Microsoft Excel. The calculation considered the load of wind and pedestrians’ movement and their effect on the dynamics of the construction. The phases of development were also considered. Assessments of coupled cross-section, main beams of steel construction, tension systems and selected construction joints were executed in a static calculation. Moreover, a design of a bearing and a bridge plug joint. Finally, a drawing documentation and a final report were prepared in regards with the requirements. The construction design and its assessment were executed according to valid standards.
|
guest ::
