|
|
The Influence of different Types of Fiber-reinforcement on the Behavior of Concrete Slabs
Wünsche, Dominik ; Žítt, Petr (referee) ; Kocáb, Dalibor (advisor)
The bachelor‘s thesis deals with the issue of concrete, specifically self-compacting concrete, fiber concrete and other types of concrete used. The work consists of two parts, the theoretical one, which will deal with the properties of the concrete. It describes the individual test methods used in the practical part. The test methods are the ultrasonic pulse method, the resonance method, the static modulus of elasticity, the compressive strength, and especially flexural strength. The second part is a practical part, which is processed by an experiment. In the experimental part, it will be mainly about carrying out tests of self-compacting concrete slabs and concrete with the addition of steel fibers. Subsequently, selected characteristics of concrete are determined and the whole experiment is evaluated.
|
|
|
Comparison of selected parameters of tensile strength of concrete
Rozsypalová, Iva ; Žítt, Petr (referee) ; Daněk, Petr (advisor)
The thesis deals with a comparison of the selected strength tension properties of the hardened concrete and finding relationships between them. This is essentially a simple tensile strength, tensile flexural strength and tensile splitting strength. The text describe the testing procedures to determine the tensile strength of concrete. Furthermore, there are presented the results of testing on different types of concrete (plain concrete, lightweight concrete, steel-fiber concrete, polymer-fibre concrete and high strength concrete). The conclusion deals with the derivation of dependancy between concrete strengths and comparing the values obtained from the available relations with the results of the tests.
|
|
|
Detection of Failures and cavities in structures using radar
Tkadleček, Petr ; Anton, Ondřej (referee) ; Cikrle, Petr (advisor)
The bachelor‘s thesis describes non-destructive testing and methods, which are used in civil engineering. It is focused on the detection of failures and cavities in concrete structures. In the first part the methods are described and compared. The second part describes experimental measurements on concrete structures, which contain failures. The results are described and interpreted. The used methods are compared. It was evaluated, which of these methods is suitable for the detection of failures and cavities in structures.
|
|
|
Influence of Air Entrainment and Curing on Development of Elastic Modulus of Concrete
Bartulíková, Radka ; Kucharczyková, Barbara (referee) ; Kocáb, Dalibor (advisor)
Master's thesis deals with influence of various factors on the concrete compressive strength and modulus of elasticity. This work concentrates mainly on the influence of early curing and air entrainment of concrete. One part of this work is the evaluation of laboratory measurement, which was carried out on cubes of standard and norm prisms. The development of elastic moduli was monitored in time to 730 days of age with respect to air entrainment and curing conditions. The second part of the experiment deals with a comparison of theoretical creep curves depending on the value of the modulus of elasticity based on different standards. Again, the air entrainment effect and influence of initial conditions are reflected.
|
|
| |
|
|
Testing early strength concrete by electronic tester
Holbová, Monika ; Kocáb, Dalibor (referee) ; Cikrle, Petr (advisor)
This project solves the creation of calibration relations for determining the compressive strength of early age concrete. It deals with news in the field of hardness methods. 36 samples were made for this experiment and tested by ultrasound and by impact hammer SilverSchmidt type L with Mushroom Plunger. The result is set of calibration relations for determining of compressive strength for different methods and their combinations.
|
|
|
Comparison of elastic moduli of building materials
Ballon, Marek ; Hubáček, Adam (referee) ; Brožovský, Jiří (advisor)
The bachelor thesis deals with the detection of static and dynamic elastic moduli of building materials, their comparison and overview of the relationships between them. Describes methods for the determination of static modulus of elasticity in the press loading and dynamic modulus of elasticity obtained by non-destructive methods, including ultrasonic pulse method and resonance method.
|
|
|
The Use of the Ultrasonic Pulse Velocity Method for the In-situ Estimation of the Quality of Concrete
Sopúch, Martin ; Cikrle, Petr (referee) ; Kocáb, Dalibor (advisor)
The primary focus of this bachelor thesis is examination of concrete properties, principally with non-destructive methods. The ultrasonic apparatus Pundit PL-200 made by Proceq Company was used for the most of non-destructive examinations of the concrete. This paper is mainly focusing on determination of a modulus of elasticity. Measuring of the properties took place in the laboratory with use of probationary entities of 100 x 100 x 400 mm and in site on concrete block situated at BUT FCE campus. The probationary entities including twists from measured block were after non-destructive examining tested in the wring to secure more accurate results. The target of the research paper, firstly, was to attest options for determination of dynamic value. Secondly, with use of decreasing coefficient determine static values of elasticity modulus on the concrete that was built-in in a construction and, consequently, test practical usage possibilities of the modern apparatus Pundit PL-200.
|
|
|
Studying the behavior of concrete at high temperatures
Tillová, Jana ; Herka, Petr (referee) ; Bodnárová, Lenka (advisor)
This master‘s thesis is focused on the study of the behavior of cement concrete at high temperatures with a focus on monitoring the impact of aggregate and cement type. This work describes the processes in aggregates and cement matrix at high temperatures. The theoretical part describes the selestion of a suitable aggregate and cement for the surroundings with potential exposure to high temperatures. In the experimental part is given design of composition of a concrete with two types of aggregates and four cements. It has been suggested 8 recipes. Changes were observed densities, compressive strength and tensile strength in bending, calculate the velocity of propagation of waves with ultrasonic pulsed method. Also evaluated the appearance of the surface samples after thermal load – cracks on the surface and measure the maximum crack width.
|
|
|
The issue of determination of the static modulus of elasticity of concrete in structures
Halamová, Romana ; Misák, Petr (referee) ; Kocáb, Dalibor (advisor)
The thesis deals with the measurement of the elastic modulus of concrete in existing structures and possibilities of applicability of equations for the calculation of characteristic values of concrete compressive strength on the modulus of elasticity. The modulus of elasticity is determined by dynamic and static methods on specimens taken from the concrete blocks, whose composition varies by a water cement ratio and varying amounts of admixtures. In conclusion, the results of the measurements are compared and the characteristic values of the modulus of elasticity is determined.
|
guest ::
