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V magistrskem delu so predstavljene spremembe pri potresnoodpornem projektiranju konstrukcij, ki jih uvaja predlog novega standarda Evrokod 8. Novosti smo analizirali na praktičnem primeru 5-etažnega jeklenega objekta iz momentih okvirov in okvirov z ekscentričnimi povezji. Preučili smo nove definicije razredov duktilnosti, faktorjev obnašanja, faktorja občutljivosti za stavbe in kontrolo vplivov teorije drugega reda, kontrole etažnih pomikov v novih mejnih stanjih ter pravila za projektiranje jeklenih konstrukcij. Pravila iz trenutnega standarda Evrokod 8 za razred duktilnosti DCH smo primerjali s predlaganimi pravili za nova razreda duktilnosti DC2 in DC3. Potresnoodporno analizo smo izvedli za ravninske modele momentnih okvirov in okvirov z ekscentričnimi povezji z metodo z vodoravnimi silami. Za momente okvire smo izvedli tudi poenostavljeno nelinearno statično analizo. Ugotovili smo, da projektiranje momentnih okvirov po predlogu novega standarda Evrokod 8 dovoljuje nekoliko lažje in vitkejše konstrukcije z manjšimi dimenzijami elementov. Pri tem za dimenzioniranje niso več merodajni vplivi teorije drugega reda, temveč omejitve etažnih pomikov. Nasprotno, upoštevanje pravil predloga novega standarda Evrokod 8 povečuje zahteve nosilnosti in stabilnosti elementov ekscentričnega povezja. Sam postopek projektiranja ekscentričnega povezja se ne razlikuje od obstoječega. Zahteve poostruje povečanje potresnega dela obtežbe potresnega projektnega stanja. Obremenitve elementov ekscentričnih povezij v DC3 in DC2 so bile večje do te mere, da je bilo najbolj smiselno povečati število povezij in ohraniti primerljive dimenzije elementov. The master thesis deals with the changes in the seismic resistance design of structures introduced by the proposal of the new standard Eurocode 8. The novelties were analysed on a practical example of a 5-storey steel building stabilised with moment resisting frames and frames with eccentric bracings. The new definitions of ductility classes, behaviour factors, the interstorey drift sensitivity coefficient and the control of second order effects, the limitations of interstorey drifts in the new limit states and the specific rules for steel buildings were examined. The code requirements from the current Eurocode 8 for ductility class DCH were compared to the proposed rules for the new ductility classes DC2 and DC3. Seismic analysis was performed for planar models of moment resisting frames and frames with eccentric bracings using the lateral force method. A nonlinear static analysis (pushover) for the moment resisting frames was also performed. It was found that the design of moment resisting frames according to the proposal of the new Eurocode 8 allows somewhat lighter and slimmer structures. In this case, the influences of the second order effects are no longer governing, but rather by the limitations of interstorey drifts. On the contrary, following the changes of the new Eurocode 8 means higher resistance and stability requirements for frames with eccentric bracings. Seismic resistance design of frames with eccentric bracings does not differ from current process. The resistance and stability requirements are intensified by the increase of the seismic part of the seismic design state. The internal forces in the frame with eccentric bracings designed for DC2 and DC3 were greater to the point that it was more reasonable to increase the number of eccentric bracings and maintain comparable element dimensions.

Glavni cilj diplomske naloge je predstavitev in uporaba novosti, ki jih na področju potresnoodpornega projektiranja armiranobetonskih montažnih stavb uvaja delovna različica novega Evrokoda 8. Predstavljene so nekatere novosti pri projektiranju montažnih stavb glede na trenutno veljavni standard. Opišemo način definicije spektrov pospeškov, določitev strižne armature v stebrih in izpopolnjena navodila za dimenzioniranje mozničnih stikov med stebri in gredami. Uporabo novega Evrokoda 8 nato demonstriramo tako, da projektiramo različice enoetažne armiranobetonske montažne stavbe. Stavbo sprojektiramo po trenutnem standardu (SIST EN 1998-1) za srednji razred duktilnosti in po delovni različici novega standarda, kjer upoštevamo novo uvedeni razred duktilnosti DC3. Pri projektiranju se omejimo na stebre in stike med stebri in gredami, ki so se med preteklimi potresi izkazali za kritične elemente konstrukcije. Prikazana je primerjava rezultatov projektiranja po obeh standardih. Sprojektirani konstrukciji primerjamo tudi z vidika nosilnosti in deformacijske kapacitete, pri čemer za določitev deformacijske kapacitete uporabimo model za mejni pomik, ki ga prav tako uvaja nova različica standarda Evrokod 8. Izkaže se, da se nosilnost stebra poveča, deformacijska kapaciteta obravnavanih stavb pa se praktično ne spremeni zaradi uporabe nove različice standarda. The main goal of the thesis is to present and use the novelties that are introduced by the draft of new Eurocode 8 in the field of earthquake-resistant design of precast reinforced concrete buildings. Some novelties in the design of precast reinforced concrete buildings in comparison to the current version of the code are presented. We describe the definition of the acceleration spectra, requirements for the shear reinforcement in columns and improved instructions on how to design a dowel connection between a column and a beam. The use of the draft of the new Eurocode 8 is then demonstrated by designing variants of a single storey reinforced concrete building. The building is designed for ductility class medium according to the current standard (SIST EN 1998-1). In addition, it is designed according to the working draft of the new standard, where the newly introduced ductility class DC3 is taken into account. The design is limited to columns and beam-to-column connections, which proved to be the critical structural components in past earthquakes. A comparison between the results of the design is presented. The designed structures are compared in terms of strength and deformation capacity. The deformation capacity was calculated by utilizing the model introduced by the draft of the new Eurocode 8. It turns out that the strength of columns increases, but the deformation capacity is practically not affected by the design rules introduced in the draft of the new standard.

V magistrskem delu analiziramo vpliv delovne različice novega standarda Evrokod 8 na potresnoodpornost reprezentativne armiranobetonske stavbe, ki je že bila sprojektirana v skladu z obstoječo različico Evrokoda 8. Učinke standardov ovrednotimo tako, da konstrukcijo obravnavane stavbe ponovno sprojektiramo z upoštevanjem zahtev delovne različice novega standarda in ocenimo njeno potresno odpornost. V prvem delu predstavimo nosilno konstrukcijo obravnavane stavbe, geometrijo, material, modeliranje vplivov in konstrukcije ter prikažemo armaturne načrte konstrukcije, sprojektirane po obstoječi različici standarda. V drugem delu opišemo novosti pri dimenzioniranju, ki jih prinaša delovna različica novega standarda. Nato nosilno konstrukcijo ponovno sprojektiramo na projektni potresni vpliv in rezultate projektiranja predstavimo v obliki armaturnih načrtov. V zadnjem delu primerjamo potresno odpornost obravnavanih stavb. Za obe konstrukciji stavbe definiramo nelinearen model, izvedemo potisno analizo in s pomočjo metode N2 določimo vrednost pospeška tal, ki povzroči mejno stanje blizu porušitve. Vpliv potresne obtežbe modeliramo na dva različna načina, z upoštevanjem Evrokodovega elastičnega spektra in z uporabo spletne aplikacije za napovedovanje IDA krivulj. Ker smo novo konstrukcijo projektirali za razred duktilnosti DC2, so projektne potresne obremenitve večje, kar je posledica nižjega faktorja obnašanja. Posledično je večja tudi količina računsko potrebne armature. Nosilnost nove konstrukcije je zato večja, deformacijska kapaciteta pa se ne spremeni bistveno. Zato je potresna odpornost obravnavanih različič stavbe v smislu mejnega pospeška tal približno enaka. Na osnovi rezultatov potresnih analiz lahko sklenemo, da delovna različica novega standarda Evrokod 8 ne prinaša bistvenih razlik na potresno odpornost obravnavane stavbe, pri pogoju, da se nova karta projektnega pospeška tal v prihodnosti ne bo bistveno spremenila. In the master thesis, we analyse the impact of the working version of the new Eurocode 8 standard on the earthquake-resistance of a representative reinforced concrete building, which has already been designed according to Eurocode 8 standard. The effects of standards are evaluated by redesigning the building structures requirements of the working version of the new standard. In the first part, we present the load-bearing structure of the analysed building, geometry, materials and the modelling of the building and loads. Drawings of the reinforcement designed according to the existing version of Eurocode 8 standard are also shown. In the second part, we describe novelties in the design that are introduced in the working version of the new standard. The structure is then redesigned for the seismic design loads, and the design results are presented by reinforcement drawings. In the last part of the thesis, the earthquake resistance of both buildings is compared. For each building structure, a non-linear model is defined, pushover analysis is performed, and the peak ground acceleration that causes the near-collapse limit state is estimated with the N2 method. The effect of seismic action is modelled in two ways, by considering the Eurocode elastic acceleration spectrum and by using the web-based methodology for the prediction of approximate IDA curves. Because we designed the new structure for the ductility class DC2, the seismic design loads were increased due to the lower behaviour factor. As a result, the amount of calculated reinforcement is also increased. The load-bearing capacity of the new structure is, therefore, higher, but the deformation capacity does not change significantly. Thus, the earthquake resistance of the new building, if expressed in terms of ultimate peak ground acceleration, is approximately equal to that designed according to Eurocode 8. Based on the results of seismic analyses, we can conclude that the working version of the new Eurocode 8 standard does not affect the seismic resistance of the analysed building significantly, provided that the seismic design maps will not change considerably in the future.