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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 sta izdelana dva modela za oceno potresne odpornosti povprečne zidane hiše na širšem območju Škofje Loke. V začetnem poglavju obravnavamo obnašanje zidanih konstrukcij in možne porušne mehanizme njihovih elementov. V nadaljevanju je predstavljeno teoretično ozadje metode N2, ki je vključena v Evrokod 8 in s katero smo določili potresno odpornost obravnavanih zidanih objektov. Analizirali in interpretirali smo rezultate analiz za 11 hiš, ki se nahajajo v širšem območju Škofje Loke in so bile zgrajene v letih od 1970 do 1990. Na osnovi načrtov Projektov za pridobitev gradbenega dovoljenja smo vrednotili srednje vrednosti in koeficient variacije za izbrane geometrijske lastnosti stavb, ki imajo pomemben vpliv na njihovo obnašanje. Pričakovani delež tlorisnih površin sten glede na neto površino etaže znaša 11–12 %, delež efektivnih tlorisnih površin sten pa se giblje v območju 60-90 % bruto površine sten, pri čemer je odvisen od smeri objekta. Povprečen zid je širok 2,4 m, njegova efektivna višina pa znaša 80 % etažne višine objekta. V primerjavi izbranih lastnosti hiš s sorodnimi podatki, ki so dostopni na spletnem portalu e-Prostor, smo ugotovili večja odstopanja v vrednostih le teh. Nelinearno statično (potisno) analizo smo izvedli s programom 3Muri. Rezultati so pokazali, da so najbolj ranljivi medokenski slopi zidu, delno pa tudi prekladni deli. Običajno pri mejnem stanju blizu porušitve nastopa kombinacija upogibnih in strižnih poškodb. Glede na mejni pospešek smo izbrali merodajne potisne krivulje in jih normirali glede na težo objekta in njegovo višino oziroma glede na povprečno efektivno tlorisno etažno površino sten v obravnavani smeri in višino objekta. S tem smo dobili dva modela normiranih potisnih krivulj. Pričakovana maksimalna dosežena nosilnost v šibki smeri objekta znaša 15 % celotne teže stavbe oziroma dobrih 60 kN na kvadratni meter efektivne tlorisne površine sten. Prikazana je uporaba modelov na primeru dveh objektov in dodana ocena potresne odpornosti za mejno stanje močnih poškodb, ki kaže na to, da večina obravnavanih objektov ne izpolnjuje zahtev Evrokoda 8-3. Two models for seismic performance assessment of masonry houses in Škofja Loka region are developed. In first chapters the behaviour of masonry buildings under seismic actions with an emphasis on failure mechanisms of structural components are discussed. Follows an overview of the theoretical background of N2 method, which is included in the Eurocode 8 and which was used for determination of the seismic resistance of examined masonry structures. The results of numerical investigation of 11 masonry houses, built in the years from 1970 to 1990, are then presented and discussed. The project design for building permit was used to obtain input data of the buildings. The mean values and the coefficient of variation were assessed for those geometrical features of the buildings, which have great impact on the seismic performance assessment of the buildings. Expected percentage of the floor surface area of the walls in relation to the net surface of the floor varied from 11 to 12 % with respect to the direction of building. The proportion of the effective floor area of the walls is in the range from 60 to 90% of the gross surface area of the walls depending on the direction of the building. Average wall is 2,4 m wide and its effective height amounts to 80 % of the building`s floor height. It was found that the selected characteristics of houses with the corresponding data which are available on the web portal e-Prostor, are significantly different. Nonlinear static (pushover) analysis was performed by using computer software 3Muri. The results show that the combination of bending and shear damage occurred in piers and also spandrels in the region of deformation close to the ultimate limit state. Two models of the normalized expected pushover curves were obtained by taking into account the pushover curves which had a decisive impact on the seismic limit-state peak ground acceleration. The base shear was normalized by the weight of the building or with respect to the average effective floor area of the walls in the given direction and whereas the top displacement was normalized only by the building’s height. Maximum expected capacity in weak direction amounted 15 % of the total weight of the building and more than 60 kN per square meter of effective floor area of the walls. In the last chapter the normalized pushover curves were used for seismic performance assessment of two houses for which it was found that do not fulfil requirements of standard Eurocode 8-3.

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.