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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.

V diplomski nalogi sem izvedel statično analizo strešne konstrukcije spomeniško zaščitenega objekta Šenkova domačija s pomočjo programa SAP2000. Spremljal sem kronološko propadanje elementov ostrešja in izdelal parametrično študijo petih računskih statičnih modelov. Osnovni model je sestavljen iz štirih okvirjev s statičnim sistemom povezja s trapeznim vešalom z dodatnim sredinskim stebrom. Mehanske lastnosti smerkovega lesa iz ostrešja, ki so bile potrebne za statično analizo, sem pridobil z laboratorijskimi preiskavami (tlačna in upogibna trdnost, elastični in strižni modul). Raziskoval sem vpliv propadanja posameznih leg in posledično postopnega deformiranja ostrešja na nalegajoče se spodnje poškodovano kamnito zidovje in preverjal, ali je glavni razlog za poškodbe zidov ravno deformacija ostrešja. Najbolj poškodovano je severno zidovje, ki je skoraj v celoti ločeno od ostalega dela objekta. Zato sem se osredotočil predvsem na reakcije in pomike v podporah severne kapne lege, ki leži na poškodovamen zidovju. Z uporabo Evrokodov sem določil obtežbe in upošteval obtežne kombinacije za mejno stanje nostilnosti (MSN). Ugotovil sem, da se je severno zidovje deformiralo zaradi vpliva deformacij ostrešja in posledičnih sprememb prenosa obtežbe ter posedkov. To zidovje namreč nima temeljev. Postavljeno je neposredno na skale, ki ležijo v mehki prodnati zemljini. Ostrešje je bilo dolgo časa brez žlebov, hiša pa brez drenaže, zato je meteorna voda spirala slabo nosilna temeljna tla, kar je vzrok za posedanje severnega zidovja. V določenem obdobju je bilo treba severno kapno lego točkovno podpreti. To pomeni, da je bilo spodnje zidovje nekaj časa brez ugodne vertikalne obremenitve. Posledica točkovnega podpiranja so močno povečane horizontalne reakcije na SV in SZ vogalu zidovja, ki so sprožile začetek nastanka razpok severnega zidovja. This thesis presents the static analysis of the heritage protected Šenk homestead's roof structure with the use of the structural analysis program SAP2000. For this purpose I have analyzed the chronological decay of roof structure elements and made a parametrical study of six static roof structure models. The basic model has four frames with a trapeze shaped triple roof static system Mechanical parameters for the calculation of spruce elements (compressive strength, bending strength, elastical mosulus, shear modulus) for statical analysis were gained by laboratorical testing of spruce samples. I have researched how gradual decay of the roof structure have influenced the deformation of the underlying stone walls. The northern walls are the most damaged with the widest cracks and are almost completely seperated from the rest of the house. Vertical reactions and displacemants of the roof wall plate roller supports were therefore the main focus of this analysis. Dead load, live load, snow load and wind load are assesed using Eurocode standards. Static analysis is based on the method of limit state load (MSN). Analysis shows that the main reason for the north wall deformation is the influence of deformed roof structure and ground setlement. The house is without a foundation and its walls sit directly on rocks that are laying in in soft gravel soil. The house was without gutters and drainage for a long time. Rainwater was therefore able to wash away the soft subgrade causing additional subgrade subsidence. The roof wall plate had to be supported at some point in time, which means that the north wall was without vertical load and consequently constant compressive stress, that had a positive effect on it. As a result the northern wall was able to deform even more. Point supported roof wall plate caused greatly increased horizontal reactions in NE and NW corner of the north wall, that have triggered the beginning of the formation of cracks.

V diplomski nalogi analiziram možne izvedbe polno nosilnih spojev. Najprej splošno razložim pojem spoja in njihove delitve. V tretjem poglavju so razložene okoliščine v katerih uporabljamo polno nosilne spoje ter prednosti in slabosti njihove uporabe. Predstavljenih je 6 različnih možnih vrst izvedbe polno nosilnih spojev. Pri posameznih možnostih izvedbe so opisani mehanizmi prenosa obtežbe in predvidena mesta nastanka plastičnih deformacij. Na koncu so podane bistvene predpostavke in zahteve za dimenzioniranje polno nosilnih spojev, v predzadnjem poglavju pa je prikazan postopek izračuna vijačenega spoja s čelno pločevino in ojačitvenim rebrom. Possible implementations of full strength moment connections are analyzed in this thesis. Firstly the concept of connections and their classifications are presented. The third chapter discusses the circumstances in which full strength connections are to be used an also their advantages and disadvantages are shown. Six different implementations of moment connections are presented with the load paths and plastic deformations discussed for each of them. Finally basic assumptions and requirements for full strength connections design are given and in the penultimate chapter a design procedure for bolted stiffened extended endplate moment connection is shown.

V diplomski nalogi ugotavljam kako delno togi spoji vplivajo na obnašanje jeklenih okvirjev. Celotna diplomska naloga je obravnavana na primeru okvirja, ki je del izmišljenega večetažnega objekta. Najprej so dimenzionirani nosilci in stebri, nato pa je, v prvem delu računa spojev, z uporabo komponentne metode, izračunana momentna nosilnost obravnavanih spojev. Ti so zasnovani kot vijačeni spoji prečka steber s podaljšano čelno pločevino. V drugem delu je prav tako po komponentni metodi izračunana začetna togost spojev Sj,ini. S pomočjo nosilnosti ter togosti je nato definiran graf moment-zasuk, ki določa obnašanje vozlišča. V programu SCIA Engineer 2013 je nato opravljena geometrijsko nelinearna numerična analiza, kjer so spoji modelirani kot nelinearne vzmeti. Kot rezultate opazujem faktor kritične obtežbe acr, horizontalni pomik zgornje etaže konstrukcije ter zasuke spojev. Pri osnovni zasnovi spoja nato spreminjam debelino čelne pločevine in opazujem kako se s tem spreminjajo prej navedene količine. Influence of semi-rigid connections on behaviour of steel frames is analyzed in this thesis. The entire thesis is based on a steel frame, part of a fictitious multi-storey building. Firstly the beams and columns are designed, which is followed by the first chapter concerning the connections, in which the moment capacity of the connections is calculated using the component method. The joints are designed as bolted extended end plate connections. In the following part the initial rotational stiffness of the connection Sj,ini is calculated, also using the component method. Using moment capacity and stiffness, the moment-rotation diagram, which defines the behaviour of the connection, is defined. A geometrically nonlinear numerical analysis is then performed in SCIA Engineer 2013, where joints are modelled as nonlinear springs. From the results, the critical load coefficient acr, horizontal displacement of the upper storey and the rotation of joints are considered. Furthermore the thickness of the end plate is then altered and the effect on the results listed before is considered.