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V diplomski nalogi je bila izdelana ocena potresne odpornosti institutskega trakta stavbe UL FGG na Hajdrihovi ulici v Ljubljani s programoma 3Muri in SAP2000. V začetnem poglavju obravnavamo obnašanje zidanih konstrukcij med potresom in možne porušne mehanizme. Sledita opis določil Evrokoda 8-3, ki obravnava področje ocenjevanja obnašanja obstoječih stavb med potresi, ter opis postopka preverjanja potresne odpornosti zidov. V nadaljevanju je opisana poenostavljena nelinearna N2 metoda. V praktičnem delu naloge je predstavljen obravnavan objekt. Za dosego čim bolj primerljivih rezultatov modelov v obeh programih smo se z modeliranjem v SAP-u želeli čim bolj približati modelu v 3Muriju. Analiza lastnega nihanja je bila preverjena na treh modelih – modelu v 3Muriju, linijskem modelu v SAP-u ter ploskovnem modelu v SAP-u. Pri primerjavi nihajnih časov se je izkazalo, da modela v SAP-u dosežeta zgolj 67–96 % nihajnih časov modela v 3Muriju. Razlike smo pripisali različnemu podajanju masnih vztrajnostnih momentov, da bi njihov vpliv preverili, pa smo izvedli parametrično analizo. Izkaže se, da bi primerljive rezultate obeh programov dosegli s povečanjem masnih momentov v SAP-u na 220 % njihove začetne vrednosti, česar pa s fizikalno utemeljenim argumentom ne moremo upravičiti. Rezultati obenem kažejo, da sta modela v SAP-u med seboj bolj primerljiva, kot sta primerljiva posamezen model v SAP-u in model v 3Muriju. To smo pripisali uporabi različnih metod izračuna – SAP uporablja metodo FEM, 3Muri pa metodo FME. Da bi v čim večji meri eliminirali razlike med modeloma v različnih programih, smo kontrolo enakosti delovanja programov izvedli še na primeru enostavne konstrukcije brez odprtin. Izkaže se, da odstopanja res niso posledica različno definiranih elementov konstrukcije v obeh programih, zato se zdi pripis razlik različnim metodam izračuna smiseln. V nadaljevanju smo z obema programoma izvedli še nelinearno statično »pushover« analizo, pri čemer smo v SAP-u materialno nelinearnost zajeli z uvedbo plastičnih členkov. Ponovno se izkaže, da modela v različnih programih ne izkazujeta primerljivih rezultatov. In this thesis, the seismic performance assessment of the UL FGG building on Hajdrihova st. was investigated by 3Muri and SAP2000 software. In the first chapter the behaviour of masonry buildings under seismic actions are presented with an emphasis on failure mechanisms of structural components. Then follow the provisions of the Eurocode 8-3 standard, which deals with seismic assessment of existing buildings. Further on, the simplified N2 method based on non-linear static (pushover) analysis is introduced. In the practical part of the thesis the UL FGG building is presented. To achieve similar results in both programs we tried to make the model in SAP similar to 3Muri model as much as possible. Eigenvalue analysis was performed on three models – the 3Muri model, the SAP frame model and the SAP shell model. A comparison of natural periods has shown 4 % to 33 % smaller values for SAP models. The reason for differences could be in different mass moments of inertia. To check the influence of MMI, parametric analysis was performed. Results of the analysis have shown the need for enhancement of the SAP model MMI to 220 % of its original value, but this kind of adjustment cannot be physically explained. Analysis also shows that the results for two SAP models are much closer in comparison to each other than the results of any SAP model in comparison to the 3Muri model. This could be the result of different analysis methods – 3Muri using FME and SAP using FEM. In an attempt to eliminate the differences between models in both programs, a simpler model was analyzed. It turns out, the differences between models are not a consequence of the definition of structural components. More likely the difference is caused by not considering the same analysis method. Further on, the non-linear static analysis in both programs was investigated. Non-linear behaviour of the material in SAP model was modeled by defining the plastic hinges into elements of the/an equivalent frame. Again it turned out, the results of SAP and 3Muri models were far from similar.

V diplomski nalogi je izdelana ocena potresne odpornosti stare upravne stavbe Rudnika živega srebra Idrija. V prvem delu naloge je predstavljeno obnašanje zidanih stavb med delovanjem potresa in opis tipičnih porušnih mehanizmov zidov. Sledi kratek opis določil standarda Evrokod 8-3, ki obravnava področje ocenjevanja obnašanja obstoječih stavb med potresi. Po korakih je opisana poenostavljena metoda N2, ki temelji na nelinearni statični analizi. Na koncu sledi še predstavitev programa 3Muri, ki smo ga uporabili za račun potisnih krivulj. V drugem delu naloge je sprva opisana upravna stavba, ki je zgrajena iz nepovezanih kamnitih in opečnih zidov. Zaradi nepoznavanja dejanske kvalitete obstoječih materialov smo za obe vrsti zidovja iz literature privzeli po tri nabore mehanskih lastnosti. Pripravili smo pet modelov z različnimi kombinacijami vrednosti mehanskih lastnosti opečnega in kamnitega zidovja, na podlagi katerih smo ocenili potresno odpornost konstrukcije. Na osnovi deterministične analize smo ugotovili, da stavba ni sposobna prenesti pričakovanega projektnega pospeška temeljnih tal ag = 0,23 g in tako ne izpolnjuje zahtev standarda Evrokod 8. Velika ranljivost konstrukcije je bila posledica zelo nizkih vrednosti strižnih trdnosti privzetih materialov, ki smo jih skladno s standardom Evrokodom 8-3 delili še s faktorjem zaupanja CF = 1,35. Različne kombinacije mehanskih lastnosti zidovja so povzročale različne oblike porušnih mehanizmov konstrukcije. Zaradi majhnih razlik med strižnimi trdnostmi privzetih materialov se potresne odpornosti posameznih modelov niso bistveno razlikovale. Vrednosti koeficientov potresne odpornosti SRCu so variirali med 0,09 in 0,12, kar se je dobro ujemalo z vrednostjo, ki je bila ocenjena v projektu POTROG (2013). Ocenjujemo, da so mejni pospeški tal za obravnavan objekt verjetno podcenjeni, kar je posledica varnostnih faktorjev, ki jih je potrebno upoštevati v primeru nepopolnega poznavanja konstrukcije. In this thesis, the seismic performance assessment of the former administration building of RŽS Idrija is investigated. The first part of the thesis presents the behaviour of masonry buildings under seismic actions, and typical failure mechanisms of masonry walls, followed by the provisions of the Eurocode 8-3 standard, which deal with seismic assessment of existing buildings. Further on, the simplified N2 method based on non-linear static (pushover) analysis is introduced, followed by the presentation of 3Muri software. The second part of the thesis begins with a description of the administration building, which was build out of stone and brick masonry walls without adequate floor-to-wall connections. Not knowing the exact quality of the existing materials, three sets of mechanical properties for both types of masonry were obtained from the literature. The seismic performance assessment was based on five models of the structure each with different combination of mechanical properties of stone and brick masonry. The results of the deterministic analysis have shown that the building is incapable of withstanding the expected design ground acceleration ag = 0,23 g and does not meet the requirements of the Eurocode 8 standard. The great vulnerability of the structure is a consequence of very low shear strength values of the masonry, which were assessed from previous studies and, in accordance with Eurocode 8-3, divided by the confidence factor CF = 1,35. Different combinations of mechanical properties of masonry have lead to different types of failure mechanisms of the structure. Due to small differences between shear strength values of the materials the seismic resistance of our models did not differ significantly. The seismic shear coefficient SRCu was between 0,09 and 0,12 which complied with the coefficient estimated in the POTROG (2013) project. It is estimated that the limit-state peak ground acceleration is most likely underestimated, which is the consequence of safety factors that need to be considered in the case of incomplete knowledge of the structure.