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V diplomski nalogi smo na osnovi poenostavljene analize dimenzionirali potrebno armaturo v stenah objekta, zgrajenega s sistemom JUBHome. Kot osnovo za projektiranje smo upoštevali standarde in navodila za potresnoodporno projektiranje temeljnega skopa in AB sten. V prvem delu smo predstavili način določitve potresne obtežbe, navodila za potresnoodporno projektiranje in kontrole, ki jim je potrebno zadostiti, za temeljni sklop JUBHome BASE ter stene JUBHome WALL. V drugem delu smo predstavili analizo izbrane konstrukcije. Izvedli smo jo s pomočjo programa SAP2000. Kot rezultate smo dobili nihajne čase in oblike, ter obremenitev posameznih sten, ki smo jih uporabili za dimenzioniranje. V zadnjem delu je prikazan postopek dimenzioniranja stene, ki se je v analizi izkazala za kritično. Določili smo potrebno vzdolžno in strižno armaturo, ter armaturo v robnih delih. Z armaturnim načrtom smo prikazali pozicijo armaturnih palic v steni. In this thesis we have designed steel reinforcement for a structure using JUBhome system, on the basis of simplified analysis. Design of the structure was carried out according to standards and guidelines for earthquake resistant design of foundations and reinforced concrete walls. In the first part of thesis we have introduced earthquake loads, guidelines for earthquake resistant design and controls, which have to be fulfilled, when using foundation system JUBHome BASE and wall JUBHome WALL. In the second part the analysis of selected structure is described. The analysis was carried out using SAP2000 software. Vibration periods, mode shapes and loads of separate walls were the results of the analysis and were used for the design of the structure. In the last part procedure of design of the most critical wall element shown by the analysis was demonstrated. Longitudinal and shear reinforcement as well as reinforcement of edges were determined. The position of reinforcement bars has been demonstrated using reinforcement plan.

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 magistrskem delu predstavljamo postopek in rezultate potresnoodpornega projektiranja visoke armiranobetonske (AB) stavbe v skladu s standardom Evrokod 8 (EC8). Obravnavamo 22-nadstropno stavbo, ki ima mešan konstrukcijski sistem ekvivalenten stenastemu sistemu. V programu ETABS smo razvili linearno-elastičen prostorski računski model konstrukcije in ga uporabili za potresno analizo objekta, ki smo jo izvedli z uporabo modalne analize ob upoštevanju projektnega in elastičnega spektra pospeškov. Osnovna nihajna časa konstrukcije za X in Y smer znašata 2,10 s in 3,24 s, celotna projektna potresna sila pa znaša okoli 6,5 % teže objekta, ne glede na horizontalno smer potresne obtežbe. Pri verifikaciji potresne zmogljivosti stavbe smo se osredotočili na kontrolo etažnih zamikov in na dimenzioniranje AB jedra v pritličju, kjer je predvideno območje sipanja energije. Ugotovili smo, da so potresne zahteve v smislu etažnih zamikov sprejemljive le, če smo v kontroli upoštevali zamike izračunane na osnovi elastičnega spektra pospeškov. V primeru visokih stavb je takšen način kontrole zamikov smiseln. Pri dimenzioniranju AB jedra smo predpostavili srednjo stopnjo duktilnosti DCM. Vzdolžno in prečno armaturo v steni jedra smo najprej izračunali z neodvisnim "peš" izračunom v skladu s standardom EC2 in EC8, nato pa še z avtomatskim izračunom programa ETABS. S "peš" izračunom smo za potreben delež vzdolžne armature v AB jedru dobili vrednost 0,63 %, medtem ko je izračun s programom ETABS izkazal za okoli 8 % več vzdolžne armature. Na to odstopanje v glavnem vpliva različno upoštevanje razporeditve armature po prerezu. Pri izračunu prečne armature je prišlo do nekoliko večjih razlik. Z neodvisnim "peš" izračunom smo določili 166 cm2/m potrebne prečne armature v celotnem prerezu jedra, program ETABS pa je izračunal približno 22 % več prečne armature. Do takšne razlike pride predvsem zaradi upoštevanja krajše dolžine posameznih delov stene (medosna razdalja) in krajše ročice notranjih sil pri izračunu s programom ETABS. In the master's thesis, we present the procedure and results of the earthquake-resistant design of a tall reinforced concrete (RC) building according to the Eurocode 8 standard (EC8). The analysed building has 22 storeys and a dual structural system equivalent to a wall system. A linear-elastic spatial model of the building structure was developed in the ETABS program and used for seismic analysis of the building, which we conducted based on the modal response spectrum method considering the design and elastic acceleration response spectra. Fundamental periods of the structure for the X and Y directions are 2,10 s and 3,24 s, and the total design seismic force is about 6,5 % of the weight of the building, regardless of the horizontal direction of the seismic load. In verifying the seismic performance of the building, we focused on the verification of interstorey drifts and the design of the reinforcement of RC core in the ground floor, where the energy dissipation area is foreseen. We found that seismic requirements in terms of interstorey drifts were met only if the interstorey drifts were calculated on the basis of the elastic acceleration response spectrum. In the case of tall buildings, such an approach of verifying interstorey drifts makes sense. In the design of the RC core, we assumed ductility class medium (DCM). The longitudinal and transverse reinforcement in the core wall was first calculated by an independent "hand" calculation in accordance with the EC2 and EC8 standards and then by an automatic calculation in the ETABS program. With the "hand" calculation, we obtained 0,63 % for the longitudinal reinforcement ratio in the RC core, while the calculation in the ETABS program resulted in about 8 % more longitudinal reinforcement. This difference was mainly influenced by the different considerations of the reinforcement distribution across the cross section. There were slightly larger differences in the calculation of the transverse reinforcement. With an independent "hand" calculation, we determined 166 cm2/m of the required transverse reinforcement in the entire core cross section, while the ETABS program calculated approximately 22 % more transverse reinforcement. This difference is mainly due to the consideration of the shorter length of individual parts of the wall (length based on centroidal axes) and the shorter lever arm of internal forces considered in the ETABS calculations.

To improve the durability and serviceability of reinforced concrete structures, different variants of dual-phase reinforcing steel were developed within the research project NEWREBAR. The investigated variant of the new material, termed DPD2 steel, has a specific microstructure that increases the corrosion resistance, but its yielding strength is less than that of Tempcore steel B500B. DPD2 steel has no yielding plateau, which is characteristic of conventional reinforcing steel. Thus, it was investigated whether the current building codes can be used to design earthquake-resistant concrete structures reinforced by DPD2 steel bars. For this reason, three multi-story reinforced concrete frame buildings were designed according to Eurocode by considering DPD2 steel and, for comparison reasons, Tempcore steel B500B. Based on the nonlinear model, which was validated by cyclic test of columns, the seismic performance of DPD2 buildings was found to be improved compared to those designed with conventional B500B reinforcing steel. This can mainly be attributed to the substantial strain hardening of the DPD2 steel, which increases the overstrength factor of the structure by about 10%. However, for the improved seismic performance, the amount of steel in DPD2 buildings had to be increased in the design by approximately 20–25% due to the smaller yield strength of DPD2 steel. Nevertheless, it was demonstrated that Eurocode 8 could be used to design earthquake-resistant frame building reinforced with dual-phase reinforcing steel DPD2.

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.

V magistrski nalogi je prikazan postopek projektiranja zidanih stavb na ciljno potresno tveganje. S predlaganim projektiranjem lahko upoštevamo vpliv potresnega tveganja objekta, česar v primeru projektiranja v skladu s standardom Evrokod 8 (SIST EN 1998, 2005) ni mogoče. V prvem delu naloge predstavimo izhodišča in osnovna določila projektiranja zidanih konstrukcij v skladu s standardoma Evrokod 6 (SIST EN 1996, 2006) in Evrokod 8 (SIST EN 1998, 2005). V nadaljevanju pojasnimo koncept ciljne zanesljivosti konstrukcij pri projektiranju in pomen ocene potresnega tveganja z vidika socialnih in ekonomskih posledic. V sklopu tretjega poglavja opišemo metode s katerimi lahko določimo potresno tveganje zidanih konstrukcij, kjer opazujemo verjetnost, da bodo prekoračena določena mejna stanja poškodovanosti. Tu podrobneje predstavimo tudi metode za analizo obnašanja konstrukcij s poudarkom na poenostavljeni nelinearni metodi na osnovi potisne analize. Matematično modeliranje obravnavanih zidanih konstrukcij izvedemo s poenostavljenimi nelinearnimi modeli pri čemer smo uporabili računalniška programa 3Muri in Tremuri. V nadaljevanju z inkrementalno dinamično analizo prikažemo odnos med intenziteto potresa in pomikom (IDA krivulje) na modelih z eno prostostno stopnjo. S statistično obdelavo intenzitet pospeškov iz IDA krivulj določimo mediano in disperzijo intenzitet potresov, ki povzročijo določena mejna stanja poškodovanosti. Nato narišemo krivulje ranljivosti, ki prikazujejo pogojno verjetnost prekoračitve posameznega mejnega stanja pri določeni intenziteti potresa. Na koncu izračunamo verjetnost porušitve objekta (prekoračitve mejnega stanja DS4) za obdobji enega in petdesetih let. Za izbrano zidano konstrukcijo, ki ima tri etaže in mansardo, je locirana v Ljubljani, ter projektirana glede na veljavne standarde, smo iterativno ponavljali opisan postopek izračuna potresnega tveganja in na ta način projektirali objekt. Pri tem smo za sprejemljivo verjetnost porušitve v petdesetih letih izbrali 1%, na osnovi katere ameriški predpis uvaja karte potresne nevarnosti, ki predstavljajo izhodišče za določitev projektne potresne sile. Največje sprejemljive verjetnosti prekoračitve mejnega stanja porušitve v 50 letih, ki jih predpisujejo drugi standardi, so za obravnavan primer bistveno prestroge, saj ne vključujejo upoštevanja potresnega vpliva. Izbrano zahtevano ciljno potresno tveganje dosežemo šele po peti iteraciji oziroma s peto varianto konstrukcije, kjer smo spreminjali debelino in izbrane mehanske lastnosti zidovja ter število etaž. In this master thesis we present the process of designing masonry buildings for target seismic risk. Using this approach we can explicitly consider the effect of seismic risk, which is not possible in case of designing of a building on the basis of Eurocode 8 (SIST EN 1998, 2005). First we present starting points and basic provisions of designing masonry buildings according to Eurocode 6 (SIST EN 1996, 2006) and Eurocode 8 (SIST EN 1998, 2005). Next we explain the concept of target reliability of constructions in design phase and the importance of seismic risk assessment from the point of view of social and economic consequences. In the third chapter we describe methods for seismic risk assessment of masonry buildings in terms of probability of exceedance of damage limit states. We also present in more detail the methods for seismic response analysis with an emphasis on the pushover-based method. The investigated masonry buildings were modeled by simplified nonlinear models by using software packages 3Muri and Tremuri. In the following we show relation between earthquake intensity and drift (IDA curves) on single degree freedom models (SDOF). With statistical analysis of intensity of the acceleration, which were obtained from IDA curves, we determine the median and dispersion of the earhquake intensities, which cause specific damage limit states. Then we draw fragility curves, which present conditional probability of exceedance of individual damage state at certain earthquake intensity. At the end we calculate the probability of collapse risk (exceedance of damage state DS4) for periods of one and fifty years. For the selected masonry building, which has three floors and a loft, is located in Ljubljana, and designed in accordance to Eurocode 8 (SIST EN 1998, 2005), we have iteratively repeated the above described calculation procedure of seismic risk and we designed the building in this maner. We have chosen 1% for the acceptable colapse probability in fifty years, based on which the USA regulation forms the maps of seismic hazard, which are the basis for determination of design seismic forces.The highest acceptable probabilities of exceeding of ultimate limit state in fifty years, that are regulated by other standards, are for the selected example too strict, since they are not accounted for the effects of earthqukes. We achieve the required target seismic risk after fifth iteration or with fifth building variant, where we were changing wall thickness, selected mechanical properties of masonry and number of storeys.

V magistrski nalogi projektiramo armiranobetonsko povezano steno 16-etažne stanovanjske stavbe. Nosilno konstrukcijo stavbe predstavljajo povezane in nepovezane stene ter dva okvira. Povezane stene oziroma stene z odprtinami so zaradi velike nosilnosti in togosti primerne za konstrukcijske elemente v visokih stavbe, vendar je razumevanje potresnega odziva takšnih sten še vedno pomanjkljivo, kar se odraža tudi v standardu za projektiranje potresnoodpornih stavb Evrokod. Obravnavana stena je sestavljena iz sedem slopov, ki so povezani z gredami. V prvem delu naloge stavbo modeliramo in analiziramo v programu ETABS 2015. Zasnova stavbe ni ustrezala zahtevam standarda, saj so bile tlačne osne sile ob vpetju sten prevelike. Da bi rešili to pomanjkljivost, smo odstranili nekatere elemente in spremenili materialne karakteristike ter dimenzije preostalih elementov. V nadaljevanju preučimo negotovosti glede prenosa potresne obtežbe na grede z dvema mehanizmoma. Pri prvem mehanizmu prenosa potresne obtežbe upoštevamo, da so grede obremenjene zaradi potresne obtežbe, pri drugem mehanizmu pa je predpostavljeno, da se grede pri potresni obtežbi močno poškodujejo in da se nato vsa potresna obtežba prenaša na slope. Rezultati analize kažejo, da se z odstranitvijo gred nihajni čas poveča skoraj za 100%, konstrukcija pa postane torzijsko podajna. Nato določimo armaturo v vseh elementih stene z upoštevanjem prvega mehanizma prenosa potresne obtežbe. Izkaže se, da je tako določena vzdolžno armaturo ob vpetju večine slopov podcenjena za približno 25% glede na armaturo, ki je posledica potresne obremenitve drugega mehanizma prenosa potresne obtežbe. The Master’s thesis presents the design of the reinforced concrete coupled wall of a 16-storey residential building. The structure of the building is composed of coupled and uncoupled walls and two frames. Reinforced concrete coupled walls have high resistance and stiffness and are therefore suitable for taller buildings, but the seismic response of such walls is not yet well understood, which is also reflected in the Eurocode standard. The analyzed coupled wall is assembled of seven piers, which are connected by beams. In the first part of the thesis, the building is modelled and analyzed by ETABS 2015. Due to the large compression forces at the base of the walls, it was found that the structure did not comply with the code. Based on the results of the analysis, it is concluded that the structural design of the building is not suitable. A better design is then achieved by removing some structural elements and by changing the material and geometric characteristics of the remaining elements. In the second part of the thesis the uncertainty of the transfer of seismic action to the coupling beams is examined. The first mechanism takes into account the transfer of seismic action also by the coupling beams, while the second mechanism assumes that the beams are severely damaged during an earthquake and that all the seismic action is then transferred to the piers. Results of the analysis show that by removing the beams, the period of vibration increases for almost 100% and the structure becomes torsionally flexible. In the basic case, the vertical and horizontal reinforcement is determined by considering the first mechanism of transfer of seismic action. It is shown that the reinforcement of the piers at the base appears to be underestimated by about 25% relative to the reinforcement which corresponds to the second mechanism of transfer of seismic action.

Magistrsko delo obravnava potresno odporno projektiranje dvoetažne armiranobetonskelesene stavbe. Stavba je zasnovana tako, da sta spodnji dve etaži betonski, zgornji mansardni del pa je lesen. Betonski del konstrukcije je sestavljen iz sten in plošč. Stene so razporejene po obodu stavbe in okoli stopnišča ter dvigala. V nadstropjih je del konstrukcije previsen. Pri lesenem delu konstrukcije obravnavamo dve konstrukcijski zasnovi, ki ju med seboj primerjamo. Prvo zasnovo sestavljajo momentni okvirji, ki se členkasto pritrjujejo na betonski parapet, drugo pa stebri, ki so vpeti v betonski parapet, nanje pa se členkasto pritrjujejo špirovci. Horizontalno stabilnost druge zasnove dosegamo z leseno ploščo, ki predstavlja diafragmo strešne konstrukcije. Po rezultatih potresne analize se odločimo za drugo zasnovo, ki jo izboljšamo tako, da ji dodamo jeklena povezja. Magistrsko delo je razdeljeno na tri dele. V prvem delu je predstavljena konstrukcija, uporabljeni materiali in obtežba. Drugi del obravnava rezultate potresne analize in dimenzioniranje konstrukcije na potresno obtežbo, tretji del pa analizo in dimenzioniranje na stalna in začasna projektna stanja. Iz rezultatov analize ugotovimo, da s predvideno zasnovo zadostujemo pogojem mejnih stanj uporabnosti in mejnih stanj nosilnosti. Master thesis describes earthquake-resistant design of two story building with open loft space. Two stories are made of reinforced concrete, while loft is made of timber elements. Concrete part of the building consists of walls and slabs. Walls are distributed along the outer perimeter of the building, around the staircase and elevator. Building is cantilevered in upper stories. Two types of structural systems were investigated for the timber part of the building. First system consists of rigid frames which are hinged to concrete parapet. Second system consists of columns which are fully supported with concrete parapet. Roof beams are hinged to the columns. Horizontal stability of the structure is provided with timber slab, which acts as diaphragm of the roof structure. After seismic analysis we decide for second structural system, which is improved with steel bracings. Master thesis consists of three parts. The structure, materials and loads are described in the first part. Follows results of seismic analysis and design, while in the third part, the analysis and design of structure under permanent and variable loads are presented. Considering analysis results we come to the conclusion that the structural system meets requirements of ultimate limit states and serviceability limit states.

V doktorski disertaciji smo predlagali iterativni postopek in zaključen izraz za izračun projektnega pospeška tal na osnovi ciljne zanesljivosti. Ta način omogoča vpogled v odnos med ciljno zanesljivostjo, povratno dobo projektnega potresa, nosilnostjo in deformacijsko kapaciteto objekta. Projektni pospešek tal na osnovi ciljne zanesljivosti smo uporabili kot osnovo za izpeljavo faktorja obnašanja. Z novo definicijo faktorja obnašanja smo razložili t.i. »empirično komponento« faktorja obnašanja, saj smo na osnovi ciljne zanesljivosti pojasnili, da mora biti faktor obnašanja za običajne objekte precej manjši od produkta redukcijskega faktorja dodatne nosilnosti in duktilnosti. Nova definicija faktorja obnašanja zato omogoča bolj racionalno odločitev glede prave vrednosti faktorja obnašanja in izračun faktorja obnašanja za poljubno izbrano potresno tveganje, kar smo demonstrirali na primeru večetažne armiranobetonske okvirne stavbe s privzeto srednjo stopnjo duktilnosti. Za obravnavan primer smo pokazali, da faktor obnašanja, ki ga predpisuje Evrokod 8, približno ustreza ciljni verjetnosti porušitve 5∙10-5. V drugem delu disertacije smo preučevali vpliv projektnih dejavnikov po standardu Evrokod 8 na potresne parametre konstrukcije. Za obravnavane konstrukcije se je izkazalo, da imajo projektni dejavniki, ki navadno zahtevajo precej dela projektanta, relativno majhen vpliv na potresne parametre konstrukcij. Po drugi strani pa imajo projektni dejavniki, ki zahtevajo relativno malo dela (npr. upoštevanje projektnih vrednosti materialnih karakteristik), razmeroma velik vpliv na potresne parametre konstrukcij, kar bi lahko bil eden izmed vzrokov za modernizacijo postopkov potresnoodpornega projektiranja stavb. V disertaciji smo preučevali tudi možne pristope za izračun projektnih prečnih sil na osnovi ciljne zanesljivosti in nelinearne dinamične analize. Ugotovili smo, da moramo strižno porušitev praktično preprečiti, če želimo, da morebitne strižne porušitve stebrov nimajo vpliva na verjetnost porušitve. Na ta način smo potrdili načelo metode načrtovanja nosilnosti, čeprav se je izkazalo, da je projektna prečna sila, ki je določena v skladu s standardom Evrokod 8, včasih podcenjena. Strižna porušitev je bila tudi v teh primerih preprečena, vendar le zaradi upoštevanja kriterija o minimalnem deležu armiranja. Zato smo predlagali alternativni postopek za določitev projektnih prečnih sil na osnovi inkrementne dinamične analize, ki se izvede za skrbno izbrane akcelerograme. A new methodology for the calculation of the risk-targeted design peak ground acceleration has been proposed. The closed-form solution of this methodology provides a useful insight into the relationships between seismic risk, the return period of the design earthquake, the strength and deformation capacity of the building. It can thus provide a basis for the derivation of risk-targeted behaviour factor, which can be used to explain the so-called empirical component of the conventional behaviour factor. The first part of the dissertation clearly shows that, in order to achieve adequate collapse safety of new buildings, the value of the behaviour factor should be much smaller than the product of overstrength and ductility reduction factor. This new definition of the behaviour factor thus allows for more rational decisions about what the adequate values of the behaviour factor are, and better estimations of the behaviour factor for a selected collapse risk. This was demonstrated for the case of a reinforced concrete frame building with prescribed ductility class medium. It is demonstrated for the building in question that the behaviour factor pursuant to Eurocode 8 nearly corresponds to a target collapse risk of 5∙10-5. The second part of dissertation explores the impact of design factors on the seismic response of structures. It was shown for the analysed structures that those design factors, which are usually derived upon extensive consideration by the designer, often only have a small impact on the seismic performance of a structure. On the other hand, the application of simple design factors (e.g. design values of the material characteristics) can significantly improve the calculated seismic response of a structure, even though some designers are not even aware of these design factors. This suggests that standards dealing with earthquake-resistant design of buildings could perhaps be modernized. In the last part of the dissertation, some possible approaches to the calculation of design shear forces were examined based on target reliability and nonlinear dynamic analysis. It was found that the shear failure of columns has to be prevented in order to ensure that the impact of this type of failure is neglectable in the context of collapse risk. This confirms the adequacy of the capacity design approach. However, it is discussed that shear failure of columns designed in line with Eurocode 8 is sometimes prevented due to minimum requirements for shear reinforcement and not due to the design shear force, which is estimated on the basis of the capacity design approach. Hence, a methodology was proposed for the estimation of design shear forces based on incremental dynamic analysis. It was shown that merely a few carefully selected ground motions can suffice to estimate the maximum shear forces in columns.

Med močnim potresom s pridom izkoriščamo sposobnost plastičnega obnašanja duktilne armiranobetonske konstrukcije, ki jo projektiramo z uporabo metode načrtovanja nosilnosti, pri čemer projektne potresne sile določimo z upoštevanjem razpokanja armiranobetonskih konstrukcij. Način določitve togosti razpokanih prerezov se v predpisih razlikuje. Vpliv različnega modeliranja razpokanih prerezov smo v diplomski nalogi preučevali na primeru 6-etažne armiranobetonske okvirne konstrukcije. Definirali smo 9 računskih modelov. Razlike v modelih se nanašajo na modeliranje togosti razpokanih prerezov ali sodelujoče širine pasnice gred v skladu z različnimi standardi in smernicami za potresnoodporno projektiranje stavb. V dveh modelih smo upoštevali, da se efektivni vztrajnostni moment spreminja vzdolž konstrukcijskih elementov, zato smo po elementih upoštevali spremenljivo redukcijo togosti, ki je bila vezana na moment na meji tečenja armature, oziroma je bila izračunana na osnovi predvidene deformacijske linije prereza pri projektni potresni obremenitvi. Takšen pristop k modeliranju zahteva iteracije. Pri primerjavi razultatov analiz ugotovimo, da dobimo za modele, ki upoštevajo na poenostavljen način enotno redukcijo togosti po celotni konstrukciji, precej podobne rezultate. Za model v katerem izračunamo vztrajnostni moment razpokanega prereza na težišče nerazpokanega prereza, dobimo precej neuporabne rezultate, saj se redukcije togosti za zelo različno razpokane prereza veliko ne razlikujejo. V primeru izračuna efektivnega vztrajnostnega momenta na težišče razpokanega prereza, pa dobimo nižje efektivne togosti, ki se po konstrukciji spreminjajo. Tako dobimo podajnejši model, ki nam v primerjavi z modelom po EC8 daje manjše količine potrebne armature, saj je celotna potresna sila za 29 % nižja, izračunani pomiki konstrukcije pa so večji, saj je maksimalni zamik etaže za 24 % višji (celotni pomik na vrhu pa za 43 %). Ker je za dimenzioniranje okvirov običajno merodajna kontrola pomikov (MSU), daje ta model rezultate na varni strani, vendar so po drugi strani projektne potresne sile manjše. Kateri postopek je bolj primeren za projektiranje bi lahko ovrednotili le z oceno verjetnosti porušitve objekta, kar pa presega okvire te diplomske naloge. In the case of strong earthquakes, the ability of inelastic response of ductile reinforced concrete buildings is of great importance in order to assure adequate collapse risk of structures, which are designed with consideration of the capacity design principles and the design force, which is obtained by taking into account post-cracking stiffness of structural elements. However, there is no uniform criteria for consideration of effective stiffness of structural elements. In this graduation thesis, several approaches for determination of effective shear and flexural stiffness are presented and demonstrated by means of an example of a six-storey reinforced concrete building. Nine different models of the structure were evaluated considering various seismic design codes, two of which reflected the fact that flexural cracking varies along the element length. In the later cases, the effective stiffness of the elements corresponded either to the initation of yielding of the reinforcement or to the estimated seismic response of the structure. Therefore, an iterative procedure was required. It is shown, that the results using uniform stiffness reduction throughout entire structure have small variation and that the results for model, where effective inertia is calculated relative to centroid of uncracked section, are not representative. Calculating effective stiffness relative to centroid of cracked sections reflects in higher stiffness reduction, thus the displacement demands are larger, although design forces are often smaller. In the case of the investigated building, the base shear was reduced by 29 % and the maximum drift was increased by 24 % in comparison to values obtained in the case of model proposed by EC8. Consequently, the required amount of reinforcement is also smaller. Which model of effective stiffness is more appropriate for earthquake-resistant design could only be evaluated by estimating seismic collapse risk for the buildings, which is beyond the scope of this thesis.

Potresnoodporno dimenzioniranje armiranobetonskih konstrukcij po standardu EN 1998-1 zahteva kontrolo pogojev, ki pri potresu zagotavljajo neporušitev konstrukcije in omejitev poškodb. V diplomski nalogi je najprej predstavljeno projektiranje potresnoodpornih konstrukcij po EC8, kjer so podani principi glede določitve potresne obtežbe in analize. V nadaljevanju pa je podrobno predstavljeno projektiranje armiranobetonskih gred za srednjo (DCM) in visoko stopnjo duktilnosti (DCH), kar predstavlja glavno temo diplomske naloge. Ker programi za analizo in dimenzioniranje konstrukcij ponavadi omogočajo dimenzioniranje le po standardu EN 1992-1, je potrebno kontrolo potresnoodpornega dimenzioniranja izvesti ''peš''. Program Gredko dimenzionira armiranobetonske grede v skladu z EN 1998-1. Rezultate analize in dimenzioniranja po EC2 vnesemo kot vhodne podatke v program, ki nam nato preveri pogoje potresnoodpornega dimenzioniranja in poda izpis rezultatov, iz katerega je razvidna izpolnjenost pogojev in rezultati dimenzioniranja strižne armature. Omogočena je kontrola upogibnih nosilnosti v kritičnih in izvenkritičnih območjih, kar programu zagotavlja celovitost dimenzioniranja betonskih gred. Grafična oblika algoritma nazorno prikazuje potek projektiranja in dimenzioniranja gred. Za izdelavo aplikacije sem uporabil program MATLAB. Uporabniku prijazen način dela s programom Gredko omogoča uporaba Matlabovega grafičnega vmesnika. V nalogi je poleg klasičnega programiranja funkcij predstavljen tudi princip dela in programiranja grafičnega vmesnika. Program sem testiral s primeri, rezultate pa primerjal z rezultati dobljenimi na drug način. S prvim primerom sem pokazal potek dela s prikazom pogovornih oken, pri ostalih dveh pa so prikazani vhodni podatki in primerjava rezultatov. Earthquake resistance design of reinforced concrete beams in accordance with EN 1998-1 requires the non-collapse and the damage limitation under the design seismic action. The earthquake resistance design in accordance with EC8 is introduced in the beginning. The continuation of diploma thesis introduces the designing of reinforced concrete beams for medium ductility class (DCM) and high ductility class (DCH) in details. In most cases, programs and applications for construction analysis and design enables designing only in accordance with EN 1992-1, the controls of earthquake resistance design must be done by hand. Application called Gredko, designs reinforced concrete beams in accordance with EN 1998-1. Analysis and designing results by EC2 are input parameters for application Gredko, where the conditions of earthquake designing are checked. The completion of designing conditions and results of shear reinforcement determination are visible on output results list. Design resistance to bending in critical and uncritical sections enables the program a completion of designing concrete reinforced beams. Graphical layout of algorithm evidently shows the procedure for beams designing. Program MATLAB was used for making out application. User-friendly way of working with application Gredko is enabled by MATLAB tool, called graphical user interface development environment. The diploma thesis, besides introducing classical programming of functions also introduces principles of working and programming the graphical user interface. Application Gredko was tested by examples and results were compared with results from different analyses. In the first testing example, a procedure of working with application is introduced with interactive windows by other two examples input parameters and results comparison are shown.

V diplomski nalogi naredimo potresno analizo dvoetažne armiranobetonske skeletne stavbe z opečnimi polnili na območju Kamnika. Zgradba je bila projektirana leta 1978 z upoštevanjem takrat veljavnega pravilnika za gradnjo objektov na potresnih območjih. V prvem delu diplomske naloge smo povzeli osnovne člene pravilnika, ki je bil veljaven v času projektiranja konstrukcije, in nato še izbrana pravila Evrokoda s poudarkom na vrednotenju vpliva opečnih polnil v procesu projektiranja konstrukcije. Za obravnavano konstrukcijo smo potresne sile računali po obeh standardih, pri čemer smo v primeru uporabe Evrokoda 8 račun naredili z upoštevanjem treh različnih modelov konstrukcije. V osnovnem modelu smo za grede upoštevali kvadratne prereze gred ter zanemarili vpliv opečnih polnil. V ostalih dveh modelih smo grede modelirali z upoštevanjem sodelujoče širine plošče pri čemer smo enkrat vpliv opečnih polnil zanemarili, drugič pa smo jih modelirali z nadomestnimi diagonalami. Vse analize smo vršili s programom ETABS in SAP2000. Ugotovili smo, da so bile projektne potresne sile po pravilniku, ki je veljal v času projektiranja objekta, približno trikrat manjše od potresnih sil izračunanih po Evrokodih. Posledično znaša količine vzdolžne armature v stebrih pritličja približno petino računsko potrebne armature po Evrokodih, v zgornjem nadstropju pa približno tretjino potrebne vzdolžne armature po Evrokodih. Razlika bi bila še večja, če bi pri projektiranju stebrov in gred upoštevali vsa določila metode načrtovanja nosilnosti, ki jih predvideva Evrokod 8. Upoštevanje polnil pri modeliranju konstrukcije, je zmanjšalo nihajni čas od 25% do 50% glede na nihajni čas okvirne konstrukcije, vendar so projektne potresne sile za obravnavan primer stavbe ostale nespremenjene. In thesis, the seismic analysis of two-storey office building in the area of Kamnik is performed. The building, which was designed in 1978 by using the then applicable rules for earthquake-resistant design of buildings, consisting of reinforced concrete frame and masonry infills. Basic articles of regulation valid in 1978 are firstly presented. Follow explanation of the Eurocodes with an emphasis on rules which address the consideration of the effects of masonry infills. In the second part of the thesis, the design seismic forces are calculated according to both standards, while in the case of Eurocode 8, the design seismic forces are assessed by using three different structural models. In addition to base case model, where beam cross sections were considered rectangular, the beam cross sections were modelled with consideration of the effective width of slab, firstly without consideration of the effect of masonry infill and secondly with consideration of infills, which were modelled by diagonals. All analyses were performed by ETABS and SAP2000. It was found that the design seismic forces according to the regulations from the time of the design of the facility were approximately three times smaller than the design seismic forces calculated according to Eurocodes. As a result, the amount of longitudinal reinforcement in the columns of the ground floor was around one-fifth of the required reinforcement according to Eurocodes, while in the top floor the amount of reinforcement in the columns was around one third of the required longitudinal reinforcement based on Eurocodes. The difference would be even greater if the design of the columns would account all the provisions of Eurocode 8. Consideration of infills in the structural model, decreased the vibration periods of the structure from 25% to 50% relative to the period obtained in the case of bare frame, but the design seismic forces for the case under consideration remained unchanged.

V diplomski nalogi obravnavamo šestetažno armiranobetonsko stavbo z dvema kletnima etažama. Cilj naloge je ugotoviti razliko v potrebni količini armature v nosilnih elementih stavbe, če jo določimo glede na obremenitve iz potresnega projektnega stanja z upoštevanjem pravil standarda SIST EN 1992, ali z upoštevanjem obeh standardov SIST EN 1992 in 1998, ki predpisuje strožje konstrukcijske zahteve in predvideva uporabo postopka načrtovanja nosilnosti, kar povečuje varnost pri projektiranju. Najprej so povzete osnove projektiranja potresnoodpornih objektov, v nadaljevanju diplomske naloge pa je opisano modeliranje objekta in analiza, ki med drugim zajema kontrolo vpliva teorije drugega reda in kontrolo etažnih pomikov. Analiza je izvedena s programom SAP2000, prav tako tudi dimenzioniranje okvirjev po SIST EN 1992. Za dimenzioniranje vzdolžne armature sten je uporabljen program DIAS. Dimenzioniranje po SIST EN 1998 je izvedeno z upoštevanjem dejstva, da gre pri obravnavani konstrukciji za konstrukcijski sistem nepovezanih sten v obeh smereh. Izbrana je srednja stopnja duktilnosti (DCM), ki smo jo upoštevali tudi pri elementih znotraj toge vkopane kleti. Primerjava rezultatov kaže, da je po SIST EN 1998 potrebno več armature, kar je še posebej očitno pri stenah, kjer se navpična armatura skupno poveča za 37 %, vodoravna pa za 27 % glede na SIST EN 1992. The thesis deals with a design of a six-storey reinforced concrete building with a two-storey basement. The main objective was to evaluate the difference in the required amount of reinforcement, if determined based on the design seismic action with consideration of the provisions of SIST EN 1992 standard or with consideration of provisions of SIST EN 1992 and 1998. The latter aproach increases the design safety due to more restrictive design requirements and due to the prescribed use of capacity design method. Firstly, the basis of earthquake-resistant design of reinforced concrete buildings is summarized in the thesis, followed by the description of the building's model and analysis, which, among other things, involves checks of the second order effects and the check of the serviceability limit state. Computer program SAP2000 was used for the analysis and partly for the design of the building, whereas walls were designed with computer program DIAS. The structural system of the building in both directions is an uncoupled wall system, which was taken into consideration for the design according to SIST EN 1998, where ductility class medium (DCM) was assumed. Comparison of results showed that more reinforcement is needed when SIST EN 1998 provisions are applied. This was the most evident for walls, since the increase of longitudinal and transverse reinforcement with respect to that based on SIST EN 1992 amounted to 37 % and 27 % respectively.

V diplomski nalogi je obravnavano področje potresne analize montažnih hiš. Analizirana je poenostavljena različica dvoetažne hiša z leseno nosilno konstrukcijo, ki ga je podjetje RIMA HIŠE d.o.o. izvedlo v letu 2013. Poenostavitev geometrije smo uvedli zaradi veljavnosti uporabe poenostavljene metode analize konstrukcije. Pri delu sem se osredotočil na problematiko določanja togosti stikov med leseno steno in betonskim temeljem, kjer je v statičnem poročilu predvidena uporaba kotnikov tipa KR285 in AE116 ter med leseno steno in leseno medetažno konstrukcijo, kjer so predvideni kotniki tipa KR285 in ABR70. V nalogi sem primerjal dobljene rezultate podajnih stikov z rezultati analize, kjer sem upošteval toge stike. Potresna analiza je bila izvedena z metodo s horizontalnimi silami v skladu s standardom Evrokod 8. Izkazalo se je, da modeliranje podajnosti stikov ne vpliva bistveno na obremenitve v stikih, vendar je podajnost stikov pomembna za pravilno oceno pomikov. In the thesis precast timber houses are addressed. Analyzed is a simplified version of two-story house, which is located in Ajdovščina and which was built in 2013 by RIMA HIŠE. An emphasis is given on modeling of the joints between the wooden structural components and concrete foundation, where project design document prescribed connectors of type KR285 and AE116, and joints between wooden wall and wooden floor panel, where project design document specifies the connectors of type KR285 and ABR70. The effective stiffness of the joints was assessed on the basis of experimental results for similar connectors. For comparison, a model with rigid joint was also analyzed. All analyses were performed on the basis of lateral force method in accordance with Eurocode 8. It had been shown that the consideration of the flexibility of joints between structural components did not have significant impact on the seismic demand of the connectors, while the consideration of the flexibility of connectors is important for the assessment of displacement.

Stanovanjska hiša, ki bo zgrajena iz lesenih okvirnih sten polnjenih z balami slame, je bila projektirana na potresno obtežbo na podlagi eksperimentalnih preiskav strižne nosilnosti stenskega elementa dolžine 230 cm. Stenski segment z in brez okenske odprtine smo obtežili s stalno navpično obtežbo ter ga nato v vodoravni smeri obremenjevali s kvazi-statično ciklično obtežbo, s katero največkrat na enostaven način uprizorimo vpliv potresne obtežbe na nosilno konstrukcijo objekta. Izmerjeni odziv stenskega elementa smo uporabili za določitev osnovnih materialnih karakteristik računskega modela, ki smo ga izdelali za obravnavano nosilno konstrukcijo. Računska analiza je bila izvedena s programom SAP 2000 verzija 8 nonlinear. Pri izračunu so bila upoštevana navodila standardov EC8 in EC5. Obravnavana naloga poleg izračuna nevsakdanje nosilne konstrukcije na potresno obtežbo vsebuje tudi pregled različnih načinov gradnje, zgodovino tovrstne gradnje ter opis gradbeno- fizikalnih lastnosti različnih sistemov pri uporabi bal slame. A tenement house, which will be built from wood-frame walls filled with straw bales, was designed to be seismic resistant on basis of experimental research results of shear strength of a test panel 230 cm long. Test panel with a window opening and a test panel without an opening were vertically stressed and horizontal quazistatic load protocol was applied. This load protocol omogoca... The measured response of the panel was used to determine basic material characteristics which were applied to the calculation model that was made to... The analysis was made with the help of computer program SAP 2000, version 8 nonlinear. During the calculating process instructions of standards EC8 and EC5 were considered. The assignment ...In my work I also reviewed different methods of building with straw bales, history of building with straw bales and I described (gradbeno-fizikalne) features of wall panels with straw bales.