Topics of doctoral theses – Materials Science, Diagnostics and Structural Reliability in Construction Industry
A doctoral thesis is the basic building block of the successful completion of doctoral studies at a university, and the study regulations of the Klokner Institute are no exception in this regard. Read the listed topics and choose the one in which you want to practice and deepen your knowledge from the lecture courses. Do not forget to contact the supervisor of the topic concerned and arrange cooperation with them.
Topics of doctoral theses – Materials Science, Diagnostics and Structural Reliability in Construction Industry
Topics of doctoral theses – Civil Engineering
Effect of fire-level elevated temperatures on the cohesion of UHPC with soft and prestressing reinforcement
(prof. Jiří Kolísko)
The interaction of reinforcement with UHPC is a basic requirement for the design and subsequent functions of load-bearing structures not only made of reinforced concrete, but also of structures made of the new high-performance cement material known as UHPC. One of the extreme loads on structures is high temperatures caused, for example, by a fire. This stress and the effect on cohesion with reinforcement has not been sufficiently investigated in the field of UHPC use so far. The aim of the PhD thesis is to obtain new knowledge about the interaction of reinforcement and UHPC during and after exposure to extreme temperatures.
Reinforcement of the masonry of the pillars with an envelope made of high-performance cement composite (UHPC)
(prof. Jiří Kolísko)
The subject of the PhD thesis is to study and describe, through theoretical-experimental methods, the possibilities of using the modern high-performance cement composite (UHPC) for static strengthening of the supporting pillars of buildings. As part of the solution, it will be necessary to verify the issue of the interaction of brick masonry elements with UHPC, i.e., materials with significantly different properties and the effect of such reinforcement.
Application of UHPC to thin-walled bridge structures
(doc. Petr Bouška)
In the doctoral thesis, the student is expected to study the design procedures of thin-walled footbridge structures made of modern high-performance composite known as UHPC using theoretical-experimental procedures. Although UHPC is cement-based, its mechanical properties make it possible to design thin-walled elements that resemble metal structures with their slenderness. As part of the doctoral thesis, the stability problems of thin-walled walls and flanges of load-bearing beams, which are not yet fully studied in UHPC, will be solved.
Evaluation of the reliability of structures exposed to extraordinary loads
(prof. Milan Holický)
Extraordinary loads caused by extreme natural influences or human activity can cause significant damage to building structures and lead to their collapse. The cost of ensuring reliability is high. The effects of these loads can only be predicted with large uncertainties. Therefore, the topic of the doctoral thesis focuses on the analysis, evaluation and optimization of acceptance criteria for extraordinary design situations caused by extreme climatic phenomena including floods, accidental impacts or explosions, or terrorist attacks. Due to significant uncertainties, probabilistic methods of reliability analysis and risk optimization are applied.
Optimization of design and operational measures in the evaluation of existing bridges
(doc. Jana Marková)
Degradation processes including corrosion and fatigue phenomena can significantly reduce the reliability of existing road and railway bridges. However, the description of the effects of these processes on the reliability of existing bridges can only be predicted with large uncertainties. Therefore, the topic of the doctoral thesis focuses on a detailed probabilistic analysis of existing bridges with regard to the effects of traffic loads, the effects of climatic loads as well as the adverse effects of the surrounding environment influencing the development of degradation mechanisms.
Risk assessment of technical systems in power engineering
(doc. Miroslav Sýkora)
Failures of power equipment that affect the availability of production blocks have high consequences. Reliability costs including diagnostics, monitoring and repairs are high. Therefore, the PhD thesis focuses on the probabilistic analysis, evaluation and optimization of the risks of the operation of degrading power equipment. In the multi-criteria approach, impacts on personal safety, economic consequences and environmental impacts are considered.
Risk assessment of technical systems in power engineering
(doc. Petr Bouška a Ing. Miroslav Vokáč, Ph.D.)
In the construction industry, glued joints are promoted for architectural reasons, e.g., in glass facade systems of buildings but also on other facade boards. The advantage is the flexibility of the glued joint, which is why local peaks of mechanical stress do not occur as is the case with a mechanical connection by a screw, pin, etc. For this reason, semi-solid adhesives are used. The thesis is focused on the description of the mechanical action in the facade system, the analysis of the viscoelastic properties of polymer adhesives, while taking into account the various effects of aging and the durability of the joints during long-term exposure to climatic conditions.
Non-destructive methods for determining the strengths of masonry elements and mortar of existing buildings, innovative hardness methods and their calibration relationships
(prof. Jiří Kolísko)
Determination of the parameters of the lumped construction materials and mortar in masonry load-bearing elements of buildings is essential for structural assessment during the implementation of reconstruction. The advantage of non-destructive methods is their ability to provide information about the structure in its large scale in an expeditious and relatively easy manner without major disturbance. The disadvantages of the methods are the uncertainties in the determination of absolute property values. The object of this dissertation is to take advantage of the significant shift in measurement technology due to the digitization of sensing and measurement evaluation to develop an innovative hardness measurement method and, in particular, to calibrate and statistically evaluate the method to make it practically applicable in the field.
Application of optical imaging methods for monitoring building structures
(prof. Jiří Kolísko)
Obtaining information on the condition of structures for the purpose of their assessment, e.g. bridges, is very often based on information obtained by visual means. Within the scope of the dissertation it is expected to analyse the development of optical methods in terms of accuracy and sensitivity and to analyse the images captured and the possibilities of their use in monitoring and evaluation of bridge structures.
Optimisation of target reliability in the design of new structures and assessment of existing structures
(prof. Milan Holický)
The directional level of reliability has a significant impact on sustainability in the construction industry, both for newly designed structures and when deciding on the reuse of existing structures. Therefore, the focus of this dissertation is on the optimization of guideline reliability levels with respect to the potential consequences of failure (human, economic and environmental safety) and the cost of ensuring reliability. Due to significant uncertainties, probabilistic methods of reliability analysis and risk optimization are applied.
The effect of climate change on the reliability of structures
(doc. Jana Marková)
Climate change can lead to increased loading effects on building structures. However, the effects of these changes can only be predicted with large uncertainties. Therefore, the focus of this dissertation is on a detailed probabilistic analysis of available past and predicted climate load data for the coming decades. A probabilistic model for the effect of climate loads with respect to climate change is developed and the associated impacts on the reliability of building structures are analysed. Loads considered include snow, wind, temperature, icing and flood loads.
Probabilistic reliability analysis of degrading structural systems
(doc. Miroslav Sýkora)
Degradation processes can act with great variability on different components of complex structural systems. For large components, it may be necessary to take into account the spatial or areal variability of the effects of degradation phenomena. Therefore, the focus of this dissertation is on detailed probabilistic reliability analysis of complex structural systems. The non-stationary effects of degradation phenomena in combination with time-varying loads such as climatic or utility loads are considered.
Viscoelastic properties of films for laminated glass
(doc. Petr Bouška a Ing. Miroslav Vokáč, Ph.D.)
The properties of polymer films for laminated glass are an important parameter for the behaviour of the glass panel in the building structure. Polymer films are made of different materials according to the intended use of the final product. They determine the resistance of the laminated glass not only under service conditions, but especially under extreme loads or the residual load capacity in case of glass breakage. The doctoral topic is focused on the investigation of the viscoelastic properties that these polymer films exhibit, i.e., their stiffness is dependent on the history, or rate, of loading as well as the ambient temperature.