Přístupnostní navigace
E-application
Search Search Close
Doctoral Thesis
Author of thesis: Ing. Lukáš Zvolánek, Ph.D.
Acad. year: 2016/2017
Supervisor: prof. Ing. Ivailo Terzijski, CSc.
Reviewers: doc. Ing. Jaroslav Navrátil, CSc., prof. Ing. Jan Vítek, CSc.
This doctoral thesis deals with the volume changes of structural concrete caused by its shrinkage. Great importance is given to the evaluation of concrete resistance against shrinkage cracking, too. A lot of physical and numerical experiments were carried out before results and conclusion of observed phenomena was publicized. The amount of physical tests and utilization rate of the experiments can be enlarged and intensified due to the usage of materials made of micro-concrete. Consequently, the design of concrete mixtures with the ordinary size of aggregate particle reflected the large knowledge obtained by micro-concrete. In this work, the effect of different fibres and its different amount was also researched. Finally, the optimized fibre concrete mixture was designed. During the testing, the unique method referred to as “Complex experiment” was developed. Obtained data from the Complex experiment allows predicting when the shrinkage cracks may occur. The final comparison between all tested materials made of concrete was performed by means of unique parameter referred to as “Critical degree of restraint”. It was proofed that the resistance of optimized fibre concrete against to shrinkage cracking is twice of ordinary concrete. Moreover, the shrinkage cracks did not occur in the developed fibre concrete during the observed period. Based on the obtained results the new scaling factors for the rheological model B4 were derived. Due to the new scaling factors, the model B4 describes the real behavior of special composite materials very well.
Concrete, micro-concrete, fibre concrete, shrinkage, shrinkage cracking, optimization, complex experiment, critical degree of restraint, concrete resistance, rheological model, model B4.
Date of defence
01.06.2017
Result of the defence
Defended (thesis was successfully defended)
Language of thesis
Czech
Faculty
Fakulta stavební
Department
Institute of Concrete and Masonry Structures
Study programme
Civil Engineering (D-K-C-SI (N))
Field of study
Constructions and Traffic Structures (KDS)
Supervisor’s reportprof. Ing. Ivailo Terzijski, CSc.
Reviewer’s reportdoc. Ing. Jaroslav Navrátil, CSc.
Reviewer’s reportprof. Ing. Jan Vítek, CSc.
Responsibility: Mgr. et Mgr. Hana Odstrčilová