Within the scope of the master's thesis, experimental research on the effectiveness of shear
strengthening with FRP systems and analytical models for evaluating their effectiveness is presented.
The selected experimental investigations focused on cyclic shear tests of individual stone and brick
walls, taken from the experimental database of the Slovenian National Building and Civil Engineering
Institute (ZAG), the Faculty of Civil and Geodetic Engineering at the University of Ljubljana, and the
Institute for Research in Materials and Constructions (ZRMK). Results from various selected tests on
strengthened walls are presented, illustrating the behavior of the walls under simulated in-plane
seismic loading. The emphasis in selecting experimental research was on various types of masonry,
including brick and stone walls, which were strengthened in different ways. Different levels of
preloading and varying boundary conditions during shear tests allowed for the development of
different failure mechanisms in the walls: flexural, shear, or mixed. The presentation of the
experimental investigations includes all crucial data necessary for preparing the analytical model
assessment, obtained from the selected experimental research, including tests on bricks, mortars used,
and masonry investigations. It is important to highlight that the first phase of the research focused on
cyclic shear testing of unstrengthen walls, followed by the repair of the same wall damages with
appropriate injection mortars, and preceded with the second phase of testing, which involved cyclic
shear testing of the strengthened walls. An overview of analytical models and guidelines is presented,
considering the Italian CNR-DT 215/2018 and the American standard ACI 440.7-22. Calculations
according to these standards were performed for the selected strengthening methods that were the
subject of the experimental investigations. Additionally, analytical assessments were also conducted
using models developed by various authors. To conduct a more comprehensive analysis, it was
beneficial to include as many results and examples as possible to more accurately assess the validity
and applicability of different models for various reinforcement configurations. The comparison
between experimental results and analytical calculations was carried out to evaluate the adequacy of analytical models for determining the contribution to shear strength of unreinforced walls under
seismic loading. The thesis also analyzed different reinforcement configurations, for which the same
analytical models were used to assess the contribution of the reinforcements to shear capacity,
revealing varying degrees of effectiveness. Each model is specifically suited to a particular
reinforcement configuration, which is reflected in the discrepancies between the analytical
assessments and the test results. The comparisons made in the thesis indicate that not every analytical
model is suitable for every reinforcement configuration.
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