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Experimental determination of the relationship between NDT parameters and the compressive strength of concrete
Kozáček, Vojtěch ; Komárková, Tereza (referee) ; Kocáb, Dalibor (advisor)
The diploma thesis deals with non-destructive testing of concrete as well as with the relationship between determined parameters and the compressive strength of concrete. The thesis is mainly focused on the ultrasonic pulse velocity method and the rebound hammer test. The experimental part of the thesis describes non-destructive tests performed on concrete blocks. The compressive strength was tested on the drill cores taken from the concrete blocks. The aim of this thesis is to find regression models of the relationship between the compressive strength and non-destructive parameters, and the subsequent analysis of the results.
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Non-destructive testing of gear-wheels
Krejčí, Martin ; Juliš, Martin (referee) ; Čech, Jaroslav (advisor)
This diploma thesis resolves aplication of particular non-destructive testing methods while producing castings of steel wheels and quality control of this process. There are described fundamentals of flaw detection, determination of flaw-generation cause and suggestions for optimalization of casting process and increasing of its quality.
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The Influence of Moisture of Lightweight Aggregate on the Concrete Properties
Pešek, Lukáš ; Lišovský, Martin (referee) ; Kocáb, Dalibor (advisor)
The bachelor thesis deals with the influence of moisture of lightweight aggregate on the concrete properties. In the experiment, test specimens from two different lightweight aggregate, and two different input moisture states of lightweight aggregate were tested. The tests were performed to determine the basic properties of lightweight concrete after 7, 28 and 90 days of maturing. Compressive strength, tensile splitting strength and depth of penetration of water under pressure were determined on cubic specimens. On the test prisms were performed tests to determine the flexural strength and dynamic modulus of elasticity. The results were processed and evaluated in tabular and graphical form to determine statistical data and formulate a conclusion.
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Practical verification of EMAT transducer parameters
Zlámal, Michal ; Havránek, Zdeněk (referee) ; Beneš, Petr (advisor)
The challenge is familiar with EMAT transducers, their basic characteristics and principles of operation. Inclusion of the theoretical knowledge acquired in Semester work 1 is based on the practical measurement of the frequency characteristics of transmitting and receiving part of laboratory made EMAT transducers. Based on the measured results should be followed by an improved design of sensor to achieve higher sensitivity with the appropriate shape of frequency response. For generating of exciting signal is expected to use LabVIEW programme environment. For credible results of the measurements in a broad range is needed to make broadband power amplifier for the transmitting and low-noise broadband amplifier for receiving part of EMAT transducer.
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Nondestructive testing in current industrial practice
Jakubcová, Eliška ; Klakurková, Lenka (referee) ; Juliš, Martin (advisor)
The bachelor thesis is focused on personnel certification of non-destructive testing according to valid standards. The theoretical part compares the Czech certification system for non-destructive testing with systems in other countries and evaluates their differences. Problems that occur during certification according to ČSN EN ISO 9712 are also discussed. In the practical part of the thesis the evaluation of the test sample is documented by means of radiographic test, magnetic particle test and leak test. At the end of the thesis the results are evaluated and discussed and also described in the form of measuring protocols.
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Preliminary survey of the historic reinforced concrete bridge
Ježíková, Pavlína ; Žítt, Petr (referee) ; Cikrle, Petr (advisor)
This bachelor thesis focuses on the preliminary survey of a bridge connecting the west and east wing of the Veveří castle. It is a structure of a very high significance because it is presumably the oldest preserved bridge made from reinforced concrete, it was completed in 1898. A visual inspection of the outside and inside parts of the bridge was performed. To examine the quality of used concrete and type reinforcement and finding out the condition of the structure, destructive and non-destructive diagnostic tests were used. Because of the historical significance of the bridge is part of the thesis devoted to the history of bridge construction and the author of the Veveří Bridge and the pioneer of reinforced concrete constructions in our country professor Josef Melan.
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Comparison of calibration relationships for determining the compressive strength of various types concrete of non-destructive testing
Kaplan, Václav ; Voves, Jiří (referee) ; Brožovský, Jiří (advisor)
The bachelor thesis deals with the copmarison of calibration relationships for compressive strength of concrete by non-destructive testing. The work describes the methods for the determination of compressive strength of concrete obtained by non-destructive methods, including rebound hammer method, ultrasonic pulse method and combined SonReb method for various types of concrete. In thesis are described species tested concretes obtained normalweigt concrete, high-performance and high-strenght concrete, light-weight concrete and self-compacted concrete. In this work are described below used types of non-destructive testing, terms of use and czech technical standarts related with non-destructive testing. For the comparisons are utilized calibration relationships of technical standarts manufacturers of test equipment and specialised literature.
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Survey and Evaluation of Reinforced Concrete Structure
Ježíková, Pavlína ; Anton, Ondřej (referee) ; Cikrle, Petr (advisor)
This diploma thesis focuses on the construction survey of the building where the University Cinema Scala and the Bolek Polívka theatre is located. The building will celebrate its 100th birthday in 2028 and its author is the builder Jaroslav Josef Polívka. The survey concerns reinforced frame constructions. The compressive strength of concrete cores and type of reinforcement was determined and non-destructive and destructive diagnostic tests were used. The first aim of the survey was to collect materials for a static report due to the planned superstructure but a visual inspection of the construction was performed and serious failures were found. For these reasons, the closure of the building was necessary. Last part of the thesis is the design of the reinforcement, if the same structure was designed according to the currently valid Eurocodes, but with the use of original materials; as well as a comparison of the designed reinforcement with the actual reinforcement.
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Creating conditions for evaluation of high-strength concrete characteristics using non-destructive testing methods
Procházka, David ; Horký,, Ondřej (referee) ; Kolář,, Karel (referee) ; Adámek, Jiří (referee) ; Brožovský, Jiří (advisor)
High-strength concrete (HSC) belongs in the recent years to frequently used types of concrete. It allows realization of static challenging structures and also shows due to its dense structure greater durability especially against aggressive media. Currently HSC construction realization abroad is not exceptional. It’s using in the Czech Republic is still limited. When realized, then in a small scale in civil engineering works. The realization of high-strength concrete structures is closely related with the concrete construction quality verification. Good efficiency of the quality control methods can provide non-destructive testing methods (NDT), especially when investigating strength of concrete built in structure. A lack on relevant data for non-destructive testing of HSC in technical and normative rules is to be considered as a significant deficiency. Evident for HSC generally is the lack in literature on deeper analysis of the factors affecting their non-destructive testing, as well a meaningful methodology or practically usable calibration relationships. HSC differs from ordinary concrete not only by used components, but also by more compact structure with different strength – elastic characteristics. Considering these differences, HSC strength prediction can not be performed by using calibration relationships developed for ordinary concrete. Moreover, the question is to what extent the current knowledge of the NDT results influencing factors can be considered as valid. The paper presents findings on the effects of the key factors affecting the measurement results of Schmidt hardness method and ultrasonic pulse method, including recommendations for the practical application of these methods. The problematic of static vs. dynamic modulus of elasticity was also solved. Calibration equations for predicting the compressive strength of HSC from the non-destructive testing parameter were elaborated, showing high cohesion among variables and practically usability.
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Ultrasonic measurement of large format tiles
Čaněk, Michal ; Topolář, Libor (referee) ; Kocáb, Dalibor (advisor)
The diploma thesis deals with influence of the used adhesive to large format tiles properties after installation. Properties on large format tiles were monitored by ultrasonic pulse velocity method. Hydraulic setting adhesives were tested in second part. Strength and modulus of elasticity were tested. The development of shrinkage over time was also monitored. The results were summarized in tabular and graphical form and were examined by simple statistical analysis to determine resulting conclusions.
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