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The Importance of Measuring Intraabdominal Pressure in Cases of Severe Acute Pancreatitis
Kural, Tomáš ; Třeška, Vladislav (advisor) ; Chytra, Ivan (referee) ; Kala, Zdeněk (referee) ; Leffler, Jan (referee)
Treatment of severe acute pancreatitis is considered to be conservative. The only generally accepted indication for surgery in severe acute pancreatitis patients is an established infection of the necrotic tissue and persisting or progressing symptoms of multiorgan failure despite the maximal intensive treatment. For surgical treatment are also indicated patients with complications of severe acute pancreatitis (erosive hemorrhage, perforation of GIT etc.). In the proposed work, attention is drawn to those cases, where the general condition of the patient deteriorates combined with a progression of ACS and where a decompressive laparotomy can improve the prognosis of the disease. In our group of 214 patients with severe acute pancreatitis, who were treated over the last six years, 70 patients were indicated for surgery. Out of this count, in 17 cases the indication for decompressive laparotomy was a raise of intraabdominal pressure up to the values of ACS together with the symptoms of organ dysfunction, 6 patients died and 11 younger patients survived.
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Reliability Analysis of Steel Columns with Encased Web in High Strength Concrete under Compression
Puklický, Libor ; Krejsa,, Martin (referee) ; Melcher, Jindřich (referee) ; Kala, Zdeněk (advisor)
The presented paper deals with a theoretical analysis of the ultimate limit state. The results of experimental research carried out at the Institute of Metal and Timber Structures headed by Assoc. Prof. Karmazinová and Professor Melcher were applied. The geometrically and materially nonlinear solution based on the Timošenko’s solution is verified by the FEM model in the computer programme system ANSYS. The random influence of initial imperfections is taken into consideration. The FEM model also includes the influence of residual stress. In the parametric study, the influence of residual stress on the cross-section plastification is researched into, its influence on the load carrying capacity limit is, together with the influence of other imperfections, the subject of the stochastic analysis, applying the Latin Hypercube Sampling (LHS). Further on, the study proves a direct effect of the concrete part of the cross-section (combination of materials steel-concrete) on the decrease of load carrying capacity limit of the beam caused by influence of the residual stress of steel. With regard to the importance of time dependent phenomena of the concrete creep for the load carrying capacity, the studies given in the Ph.D. thesis are oriented in this respect. The parametric studies of the influence of the concrete creep having applied the Standard Eurocode 2 provide both a comparison of load carrying capacity limits when using common and high-strength concrete types, and also the variability of load carrying capacities. It follows from the comparison of the statistical analysis outputs according to the design reliability conditions of the Standard EN1990 and of the approach of Eurocode 4 that the Eurocode 4 can be recommended for dimensioning of this member type. According to the studies which we carried out, the design in compliance with Eurocode 4 can be evaluated as the reliable one. A larger set of experimental data is necessary to determine the economy.
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Problems of Reliability of Steel Members Sensitive to Imperfections
Nezbedová, Anna ; Lehký, David (referee) ; Kala, Zdeněk (advisor)
This thesis deals with the problems of reliability of steel members sensitive to imperfections. Formulas for nonlinear analysis of compressed and bended members are derived. For compressed elements, there is described the issue of buckling, for bended elements it is lateral-torsional buckling. Then a statistical analysis of reliability of these problems is performed and also comparison with the approach described in Eurocode 3.
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Reliability analysis of thin-walled cylindrical tanks for crude oil storage
Serbousková, Kateřina ; Valeš, Jan (referee) ; Kala, Zdeněk (advisor)
This bachelor thesis is focused on the reliability of rotationally symmetric thin-walled cylindric tank for crude oil storage. The general form, membrane state, and balance equation of rotationally symmetric shell is described in the first part of the bachelor thesis. The second part of this bachelor thesis describes the probabilistic analysis of reliability of the tank by using Cornell's index of reliability. At the end the model of tank was created in ANSYS software, which indicates processes of stresses and deformations of the particular load.
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Nonlinear Response of Steel Structures on Statical Loading
Nezbedová, Anna ; Vlk, Zbyněk (referee) ; Kala, Zdeněk (advisor)
This paper deals with the nonlinear response of steel structures to static loads. There are formulas derived for nonlinear analysis compressed, bended and tension members. By compressed elements, there is described the issue of buckling, by the bended, it is lateral-torsional buckling and tension elements are cables. As an example there is an calculation of a suspension two spans pedestrian steel bridge under load action of asymetrical loads. As another possible calculation process, the finite elements method is described.
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