|
|
Static analysis of one joint of timber structure
Sedlák, Petr ; Gratza, Roman (referee) ; Kytýr, Jiří (advisor)
This diploma thesis deals with the numerical modeling of the nail joint of the timber roof structure and it is based on the already realized physical experiment. Totally twelve various solutions, where the isotropic and ortotropic characteristics of the spruce timber and steel components change, have been created. The final values of the joint shift obtained by using of the numerical modeling are compared with results of physical experiment. Program system ANSYS is used.
|
|
|
Analysis of membrane structures with respect to construction stages
Zajac, Zbyněk ; Kytýr, Jiří (referee) ; Lang, Rostislav (advisor)
This diploma thesis deals with problem of design and calculation of membrane structure. Design proces of light and airy structure was demonstrated on conical shaped roof in the finite element analysis program RFEM. The structure was loaded in the virtual wind tunnel in the program RWIND. Results were compared with the values given in the literature. A comprehensive guide for the design of membrane structures has been created. Subsequently, the influence of design stages on the internal forces was demonstrated. Membrane structures are very sensitive to construction stages, because it is not possible to prestress all membrane surfaces at once. Program by DLUBAL software s.r.o. was used for form-finding analysis during construction stages.
|
|
|
Algorithms for design and analysis of membrane structures
Lang, Rostislav ; Krejsa,, Martin (referee) ; Kytýr, Jiří (referee) ; Němec, Ivan (advisor)
Předkládaná práce se zabývá problematikou navrhování membránových konstrukcí, a to především s ohledem na vývoj potřebných výpočetních nástrojů v rámci MKP programů. Po uvedení základních fyzikálních požadavků jednotlivých kroků při navrhování těchto konstrukcí budou dále prezentovány vybrané či navržené algoritmy. Kapitola form finding se zabývá analýzou tvaru membránových konstrukcí. Rovnovážný tvar je odvozen od požadavku na výsledné předpětí, specifikované okrajové podmínky a aplikované zatížení. Obecně se ale tento proces zabývá i samotným hledáním rovnovážné soustavy sil v prostoru. V důsledku této skutečnosti jsou součástí popisované analýzy také vhodné stabilizační metody. V této kapitole budou prezentovány jak zvolené postupy, tak i navržená stabilizační technika specializovaná na hledání tvarů kuželových membrán. Dále je také popsán navržený algoritmus pro řešení úloh optimalizujících tvary ohybově tuhých konstrukcí, které jsou spjaty s hledáním labilních rovnovážných konfigurací. Kapitola structural analysis je zaměřená především na fenomén vrásnění membrán. Tato náhlá ztráta stability silně ovlivňuje statickou i dynamickou odezvu membránových konstrukcí. V rámci této kapitoly je představena a verifikována navržená výpočetní metoda, modulárně aplikovatelná na lineární, nelineárně elastické i plastické materiály používané pro uvedené konstrukce. Kapitola cutting pattern generation se zabývá výpočtem střihových vzorů, nezbytných pro výrobní proces membránových konstrukcí. Pro tento proces je v rámci předkládané práce navržena kombinace dvou různých metod. Zvolená posloupnost algoritmů cílí na optimalizaci poměru rychlosti, obecnosti a přesnosti výpočtu. Zmíněné kapitoly jsou doplněny jednotlivými příklady, analyzovanými pomocí popisovaných algoritmů, které demonstrují konkrétní fyzikální problémy či nezbytné implementační procesy.
|
|
|
Static Analysis of Steel Plates with Holes
Kolláriková, Simona ; Kytýr, Jiří (referee) ; Gratza, Roman (advisor)
The bachelor thesis deals with analyzing stress concentration factor for steel plates with circular holes subjected to different types of loading. Finite element analyses of uniaxial tension, biaxial tension and bending were performed, using ANSYS software. The aim of the thesis is to compare the results of the numerical analyses with available analytical solutions and to evaluate the dependence of stress concentration factor on changes in geometry of the plates or in the computational model.
|
|
|
Static Analysis of Parts of Thermoplastic Pipe Systems
Plášek, Jan ; Kuklík,, Pavel (referee) ; prof. Ing. Alois Materna, CSc., MBA (referee) ; Kytýr, Jiří (advisor)
Thermoplastic materials have significant nonlinear behaviour. The nonlinear behaviour is described by creep curves. The curves of creep modules are dependent on stress, temperature and time. The dissertation thesis deals with the approximation of the creep modules by Prony series. Subsequently three procedures are proposed to take account of creep modules. The proposed procedures are used in two applications. The first application deals with the ring stiffness value of a corrugated sewage pipe. The ring stiffness value is influenced by the creep modulus. The other one deals with a thermoplastic flange connection. The clamping force is dependent on the creep modulus of thermoplastics. The problems were solved by ANSYS program system.
|
|
|
Analysis of Thermoplastic Welded Joints
Procházka, Martin ; Kytýr, Jiří (referee) ; Gratza, Roman (advisor)
This thesis deals with analyses of thermoplastic welded joints. Experiments were performed, in which the not-welded specimens and specimens with cruciform welded joints were tested by tensile and three-point bending test. For these measurements, polypropylene and polyethylene specimens were used. Afterwards, the analyses of specimen models were made in the ANSYS programme. The results of the analyses were compared with figures of the analytic calculations and measurements.
|
|
|
Static Analysis of Textile Structures
Husáriková, Natália ; Gratza, Roman (referee) ; Kytýr, Jiří (advisor)
This work deals with the design and calculation of membrane structure for shelter placed above selected ground plan. The hyperbolic paraboloid was chosen as most optimal shape. Subsequently, three different sub-studies were conducted. In the first study, influence of mesh density on a finite element calculation model was studied. Second study deal with the effect of the geometry changes of the computational model. In the third study, deformations and tensions of membrane structure in relation to material formation calculation model was studied. For the static solution of those selected variant, structural analysis software RFEM and RF-FORM-FINDING add-on module was used. Geometric nonlinear solution was applied in the calculation.
|
|
|
Buckling Analysis of Thermoplastic Pipes
Procházka, Martin ; Kytýr, Jiří (referee) ; Gratza, Roman (advisor)
This thesis deals with buckling analysis of thermoplastic pipes. An experiment was conducted in which the pipes were encumbered in axis. During this experiment, the loading force was monitored and measured at the material stability loss. For these measurements, polyethylene, polypropylene and polyvinylchloride pipes were used. Afterwards, the static and buckling analysis of pipe models were made in the ANSYS programme. The models were created on the basis of the experiment results. The outcomes of the analysis were compared with figures of the theoretical calculations. In the ANSYS programme pipes were strained by external overpressure.
|
|
|
Static analysis of cable
Pőthe, Péter ; Kytýr, Jiří (referee) ; Vlk, Zbyněk (advisor)
This bachelor thesis deals with the static analysis of suspension cables of the suspension footbridge. The processing was done as a manual calculation as using the program system RFEM for a static finite element method from company Dlubal. The task was to determine the geometric shape of cables and the real position of suspenders, which we get after the construction of the bridge. The results were then compared with each other.
|
|
| |
guest ::
