Author, Institution: Tadas Lisauskas, Kaunas University of Technology
Science area, field of science: Technological Sciences, Civil Engineering, T002
Scientific Supervisor: Assoc. Prof. Dr. Mindaugas Augonis (Kaunas University of Technology, Technological Sciences, Civil Engineering, T002)
Scientific Advisor: Dr. Mario Rui Tiago Arruda (CERIS at University of Lisbon, Portugal, Technological Sciences, Civil Engineering, T002)
Dissertation Defence Board of Civil Engineering Science Field:
Prof. Dr. Raimondas Bliūdžius (Kaunas University of Technology, Technological Sciences, Civil Engineering – T002) – chairman
Prof. Dr. Eglė Jotautienė (Vytautas Magnus University, Technological Sciences, Mechanical Engineering – T009)
Assoc. Prof. Dr. Peter Koteš (University of Žilina, Technological Sciences, Civil Engineering – T002)
Prof. Dr. Žymantas Rudžionis (Kaunas University of Technology, Technological Sciences, Civil Engineering – T002)
Assoc. Prof. Dr. Darius Zabulionis (Vilnius Gediminas Technical University, Civil Engineering – T002)
The dissertation defence takes place online.
The doctoral dissertation is available on the internet and at the library of Kaunas University of Technology (K. Donelaičio g. 20, Kaunas).
In the modern world, the strengthening of reinforced concrete structures is a very important field of construction, which basically includes two main ways of strengthening reinforced concrete structures: the strengthening of new structures and the strengthening of existing structures. The dissertation analyses a review of state-of-the-art research on flexural reinforced concrete beams strengthened with carbon fibre and the parameters of the contact zone between carbon fibre and concrete. An experiment was performed on cracked and uncracked reinforced concrete beam strengthened with carbon fibre. The failure force, deflections and relative deformations of concrete and carbon fibre were measured for composite beams. The obtained experimental results are compared with the iteration method, ACI, ISIS and fib norms. An analytical model describing the contact force and stress between carbon fibre and concrete was proposed. The obtained results are compared with the results obtained in the theory of the built-up bars. The proposed analytical method, which can describe the bond force and shear stress for cracked (low cracking intensity) elements over the length of the element, has been supplemented. This method is easily applicable in practice, as it is possible to estimate different load cases without solving complex differential equations. The obtained results are compared by the finite element method. Parameters describing the bond between carbon fibre and concrete were analysed by FEM, and the deflection curves from the applied load were obtained, which were compared with the performed experiment.