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Options of determining the frost resistance of concrete in a structure
Jindrová, Barbora ; Vymazal, Tomáš (referee) ; Kocáb, Dalibor (advisor)
The diploma thesis deals with different methods of determining levels of degradation of concrete due to freezing, also considering the options of freeze thaw resistance determination in structure. At first the properties of concrete and possible mechanisms of concrete degradation are described – mainly the effects of freezing water in the inner structure and of the combination of freezing water and de-icing chemicals on the surface. Principle and properties of air-entrained concrete are also mentioned. An overview of the approaches that current standards use to determine the freeze-thaw resistance of concrete is listed, followed by description of the tests that are used on air-entrained concrete specimens in the main part of the thesis. A portion of the test specimens was made in moulds while the rest was obtained from structure (concrete block). The non-destructive tests used are evaluated in several different ways and their results are compared with the destructive tests. Comparison and evaluation of different approaches used to determine the freeze-thaw resistence of concrete are the main outcome of this thesis.
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Experimental study of reinforcement in light-weight concrete components
Lisztwan, Dominik ; Kocáb, Dalibor (referee) ; Vymazal, Tomáš (advisor)
This bachelor thesis describes the experimental comparison of behaviour of reinforced lightweight concrete panels. Panels are reinforced with traditional steel grid and basalt composite reinforcement. The comparison of results is based on set of data from static load tests. The results of load test are also compared to the results made with nonlinear numerical analysis by finite element method and also calculation by hand. A part of this thesis includes determination of physical and mechanical properties of used concrete.
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Experimental Investigation of the Influence of the Type of Fibres on the Behaviour of Fibre Concrete
Hanuš, Petr ; Vymazal, Tomáš (referee) ; Kocáb, Dalibor (advisor)
This diploma thesis deals with the comparison of different properties of fibre-reinforced concrete according to the type of fibres. The main monitored property is flexural strength, tested on prisms with a cross section of 150x150 mm and a length of 600 mm. Four concretes of natural aggregate and four concrete of lightweight aggregate were prepared for the experiment. There were 2 reference concrete and 6 fibre-reinforced concrete. Three types of fibres were used: steel, polypropylene and glass. More than 2500 kg of concrete was produced. The aim of the thesis is to assess the influence of fibres on the flexural strength and other characteristics of fibre-reinforced concrete.
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Risk Management Options for Testing Laboratories in the Context of Revised Standards of Management Systems
Suchý, Ivo ; Misák, Petr (referee) ; Vymazal, Tomáš (advisor)
The diploma thesis deals with analysis and assessment of risks in testing laboratories, where the work with risks is an unrecognized area. A part of the thesis defines risks according to standard revision 17025:2017. Subsequently, these risks are processed by selected methods, which are used for qualitative and quantitative evaluation. Risks determination in the thesis is based on methods Risk Matrix, Failure Modes & Effects Analysis (FMEA) and Bow Tie Analysis. Introducing possibilities and patterns of described methods to testing laboratories is the main aim of the thesis, this could be a way to increase their chance to get a new accreditation.
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Risks and Opportunities of Implementing a Corporate Social Responsibility System
Grocholová, Anna ; Koch, Libor (referee) ; Vymazal, Tomáš (advisor)
The author of the diploma thesis deals with application of methods for risks and opportunity identification and risk analysis to assess the project of implementation of Corporate Social Responsibility to the organization. Firstly, the thesis includes theoretical background about corporate social responsibility and risks management. The theoretical background serves as a support for applying methods and analyzing the necessary areas. The goal of this work is to find solutions and propose preventative measures to be used by the evaluated organization.
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Assessment of the effect of origin and the fraction of coarse aggregate for flexibility and durability of structural concrete
Hanuš, Petr ; Žalud, Oldřich (referee) ; Vymazal, Tomáš (advisor)
The bachelor thesis deals with influence of origin and fraction of rough aggregate on the durability and elasticity of structural concrete. As a criterion of durability, the frost resistance of concrete is monitored. In the theoretical part describes the types of aggregates, which are used in structural concretes. In addition, test methods are described to determine the elasticity and durability of concrete according to the test standards valid in the czech republic. In the experimental part of the thesis, seven concretes of the same consistency and strength were designed and mixed, which differed using different types of coarse aggregate. A change in elasticity during freezing cycles was observed
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The Use of Alternative Sources in the Building Industry
Dvořák, Jakub ; Vymazal, Tomáš (referee) ; Žižková, Nikol (advisor)
This bachelor thesis is focused on the use of waste as alternative raw materials in construction industry. The first part is dedicated to the historical development of waste management, to the valid legislation in the Czech Republic in 2017 and outlines the distribution of waste according to various criteria. The information about waste production and waste management is processed in the form of tables and graphs. The more extensive second part of the thesis uses theoretical knowledge in the field of waste management and on the base of the Waste Separation Catalog is composed a list of waste materials which can be used in construction industry. Further are described the possibilities of suitable waste utilization at production and also mentioned some particular construction products with their features.
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Opioids in caesarean section
Nosková, Pavlína ; Bláha, Jan (advisor) ; Málek, Jiří (referee) ; Vymazal, Tomáš (referee)
The thesis is focused on perioperative use of opioids during caesarean section. The general part is concerned with pharmacology of opioids due to their practical use during general and regional anaesthesia and postoperative analgesia with particular focus on remifentanil. Emphasis is put on the placental transfer of opioids into breast milk which has the possible influence on postnatal adaptation of the newborns and breastfeeding/lactation. The first part of the research describes current anaesthetic practice and opioid use in obstetrics in the Czech Republic according to the OBAAMA-CZ study in 2011. The second study on a unique group of 151 parturients showed that bolus application of remifentanil at a dose of 1 μg/kg at the time of 30 seconds before induction of general anaesthesia for caesarean section significantly stabilizes maternal hemodynamic parameters (blood pressure, heart rate) and reduces the stress response to tracheal intubation and skin incision. On the contrary, no influence on depth of anaesthesia (monitored by BIS) was found. But we demonstrated a slight effect of remifentanil on the assessment of postnatal adaptation of newborns at first minute after delivery. However, this attenuation was very short and in the fifth minute the results were already fully comparable to the control...
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Hemocoagulation and its influencing of contact with body cavities lining, especially pericardium
Vymazal, Tomáš ; Cvachovec, Karel (advisor) ; Stříteský, Martin (referee) ; Vaněk, Tomáš (referee)
Body cavity surgical procedures have been arising. The surgery is complex and often extending two hours on patiens with serious comorbidities and over 65 years of age. The major cavities are the thorax, abdomen and skull. Any body cavity surgical procedure is accompanied by touch of blood and biological membrane leading to release of tissue factor and effecting clot formation pathways. The blood is due to a clear site of procedure succkled out of a body and in most cases is not transfused back: that is why it does not affect the coagulation pathways. If a masive bleeding is expected a cell - saving machine could be used to recuperate and retransfuse the patient's blood. The cell -saver membrane can separate large molecules and substances (fat, blood clot) but is not able to catch various cytokines and tissue factor. These are associated with clot formation pathways disturbances. Coagulation disorder is very serious leading to a massive hemorrhage which is ussualy treated with allogeneic blood transfusion. Allogeneic blood transfusion is associated with poor wound heeling and higher risk of infection complications in postoperative period. In the first part of my work the influence of coagulation system following contact a patient ́s blood and biological body membrane was evaluated. I also wanted to answer...
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