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Earth houses provide housing solution for around 30 % of the world's population. Building with soil is cheap and supports sustainable building. Albeit present, rammed earth (RE) houses in Croatia are mostly abandoned and heavily damaged due to an insufficiently raised level of awareness of their significance. In addition, current Croatian design standards do not recognize RE as a load-bearing element, and thus do not support the construction of new or reconstruction of existing earth houses. Project RE-forMS embodies the synergy of modern design of structural walls and traditional building with RE. Data and samples from existing earth houses will be collected through field surveys. The controlled cultivation and testing of agricultural crops will define the natural fibres for strategic reinforcement of RE walls. Properties of both RE samples from the field as well as improved RE mixtures reinforced with natural fibres will be determined in laboratories. Via experimental testing the thermal and seismic performance of RE walls and mock-up houses will be tested. Measured data will be used for studies through nonlinear numerical simulations. This project is transformational with expected impact on the preservation of cultural heritage, encouraging sustainable building and developing Croatian norms for design of RE houses.

This study presents experimental testing to examine the possibility of using recycled rubber as partial replacement aggregate for structural columns. Six reinforced concrete columns having 300×300 mm cross-section and 3250 mm total length were tested under axial compression and incrementally increased reversed cyclic loading. The results indicated that rubberized concrete columns made of self-compacting concrete can behave almost like the conventional ones. However, rubberized concrete can delay and reduce the amount of damage occurring under seismic loading. This is attributed to the higher deformability of rubberized concrete compared to conventional. Results demonstrated that rubberized self-compacting concrete provides an environmentally friendly alternative to conventional concrete in structural applications.

Naziv ovog završnog rada je “Relejna zaštita 110 kv kabelskih vodova Vrboran – Sućidar“. U radu su izvršeni proraĉuni podešenja relejne zaštite u TS Vrboran, za konkretan kabelski vod “Vrboran – Sućidar 1”. Napravljen je izbor funkcija zaštite koje će se koristiti u sluĉaju nastupa meĊufaznog kratkog spoja te zemljospoja, kao i konkretnih podešenja korištenih funkcija zaštite. Zbog specifiĉnosti prikljuĉka TS Sućidar na 110 kV mrežu , proraĉuni su izvršeni za redovno te za izvanredno uklopno stanje. Pri proraĉunima su uvaženi svi osnovni kriteriji kvalitetnog rada relejne zaštite. Valja naglasiti da je kvalitetan rad sustava relejne zaštite bitan za kvalitetno funkcioniranje EES-a u cjelini., The title of this final paper is "Relay protection of 110 kv cable lines Vrboran - Sućidar". The paper calculates the settings of relay protection in TS Vrboran, for a specific cable line “Vrboran - Sućidar 1”. A selection of protection functions was made which will be used in case of interphase short circuit and earth fault, as well as specific settings of used protection functions. Due to the specifics of the connection of TS Sućidar to the 110 kV network, calculations were performed for regular and for extraordinary switching condition. All basic criteria of quality operation of relay protection are taken into account in the calculations. It should be emphasized that the quality operation of the relay protection system is important for the quality functioning of the power system as a whole.

Potresna opasnost govori o vjerojatnosti potresanja tla u određenom području i važan je ulazni podatak za razumijevanje potresnog rizika, vjerojatnosti oštećenja i gubitaka za promatrano područje Analiza potresnog rizika područja objedinjuje informacije o potresnoj opasnosti, prirodnim fenomenima, s informacijama o izloženim elementima - zgradama, infrastrukturi ili ljudima - i ranjivosti tih elemenata na buduća potresanja tla.

Okvirne armiranobetonske (AB) konstrukcije dominantno se koriste za izvodenje niskih i srednje visokih građevina na području Republike Hrvatske, te ponekad je ovakve građevine u seizmički aktivnim zonama potrebno ojačati, kako bi prema potrebi povećali nosivost, krutost i/ili duktilnost osnovne nosive konstrukcije. U ovoj disertaciji razrađena je upotreba zidanih ispuna, s različitim tipovima veza ispuna i AB okvira, kao element ojačanja osnovne AB konstrukcije za potresna djelovanja. Poznato je da prisustvo ispuna, i bez dodatnog povezivanja s okvirom, značajno mijenja dinamički odgovor konstrukcije, pri čemu elementi ispuna ne mogu biti zanemareni pri dinamičkoj ili statičkog analizi građevine. Postojeći važeći propisi ne sadrže pojašnjenja o utjecaju ovakvih ojačanih konstrukcija, sto čini ovo područje dodatno zanimljivim. Dosadašnje spoznaje pokazale su da jednolika prisutnost zidanog ispuna doprinosi većoj krutosti i nosivosti sustava, pri čemu konstrukcija doživljava manje globalne pomake, time i manja oštećenja, sto se često smatra pozitivnim učincima zidanog ispuna. S druge strane prisutnost ispuna može dovesti do lokalnih ili globalnih plastičnih deformacija osnovne okvirne konstrukcije, formirajući tako kratke stupove, posmične slomove čvorova stup-greda, ili formiranje tzv. mekane etaže, te redukcije duktilnosti pojedinih elemenata i/ili konstrukcije u cjelini, sto su dakako jedni od negativnih učinaka ispuna. Ojačanjem okvira dodavanjem ispuna u kombinaciji s međusobnim vezama nastoji se prvenstveno poboljšati međudjelovanje ispuna i okvira, koje se može promatrati i kroz doprinos duktilnosti sustava, te kroz reduciranje mogućih negativnih učinaka ispuna spomenutih ranije, na jednorasponskim jednoetažnim uzorcima. Doktorska disertacija obraduje ponašanje praznih ravninskih AB okvira, te ravninskih AB okvira ojačanih dodavanjem zidanog ispuna u kombinaciji s međusobnim vezama ispuna i elemenata okvira, za potresna djelovanja. Koristeći dosadašnje spoznaje o kompozitnom sustavu okvira s ispunom, te njihovom međudjelovanju, primarni cilj ove disertacije bio je istražiti mogućnosti korištenja zidova ispuna u AB okvirima kao metodu ojačanja, promatrajući pri tome cikličke odzive dobivene eksperimentalnim ispitivanjem pojedinih modela u svojoj ravnini. Kako bi doprinijeli razumijevanju ojačanja okvira pomoću zidanih ispuna, provedena su eksperimentalna i numerička istraživanja. Eksperimentalni dio istraživanja proveden je na 10 jednorasponskih i jednoetažnih uzoraka duktilnih i neduktilnih armiranobetonskih okvira ojačanih zidanih ispunom (šuplja glinena blok i puna opeka), te 7 srodnih referentnih uzoraka korištenih za evaluaciju ojačanja ispunom i kvalitetu veza ispuna i okvira. Uz statičko cikličko ispitivanje samih uzoraka okvira, provedeno je ispitivanje i mehaničkih karakteristika ugrađenih materijala (betona, armature, zidnih elemenata, zida, morta i kompozitnih materijala). Uzorci okvira izvedeni su u mjerilu 1:2.5 za duktilne, odnosno 1:2 za neduktilne okvire, ispitanih pri stalnim vertikalnim i uvećavanim horizontalnim cikličkim opterećenjem (engl. Static Reversed-Cyclic Test). Ispitni uzorci mogu se grupirati prema vrsti zidnog elementa (šuplji glineni blok i puna opeka), prema tipu AB okvira (duktilni i neduktilni), te tipu veza ispuna i okvira. Ovime dobivamo ukupno 6 različitih konguracija ojačanja, od kojih su pojedini primijenjeni na dva tipa ispuna. Obradom vlastitih eksperimentalnih ispitivanja prikazane su karakteristike u ponašanju svakog uzorka, te utvrđen je najpogodniji tip ojačanja za duktilne i neduktilne okvire. Za sve eksperimentalne uzorke, od kojih su 10 izvornih i 7 referentnih, provedena je kalibracija istih pomoću nelinearnih makro{modela u programu OpenSees (PEER, Berkeley, opensees.berkeley.edu). Numerički modeli temeljeni su na tzv. grednim elementima za stupove i grede, te tlačnim dijagonalama za zidove ispuna, za koje je postignuto zadovoljavajuće poklapanje cikličkih odziva u odnosu na eksperimente. Isti modeli korišteni su u numeričkoj studiji slučaja, za predviđanje dinamičkog odziva s primjenom na realnoj građevini (Tsukuba, Japan) putem IDA analiza, pri čemu su konstruirane IDA krivulje i krivulje oštetljivosti, krivulje ranjivosti, krivulje gubitaka za svaki tip ojačanja posebno, kako bi ocijenili učinkovitost pojedinog ojačanja u odnosu na referentne modele. Na kraju je ukratko prikazana i eksperimentalna studija slučaja prostorne FRAMA građevine, Model #1 i Model #2 (FRAmed-MAsonry Composites for Modelling and Standardization, framed-masonry.com), koja je izvedena u mjerilu 1:2.5, te dinamički ispitana na potresnoj platformi u institutu IZIIS (Institut za Zemljotresno Inženjerstvo i Inženjersku Seizmologiju, iziis.edu.mk), Skoplje, Makedonija. FRAMA građevina, Model #1 i #2 sadrže vrlo slične karakteristike u geometriji, vrsti ispuna i tipu ojačanja kao sto je to slučaj s pojedinim izvornim ravninskim eksperimentalnim uzorcima iz prvog dijela istraživanja. FRAMA Model #1 reprezentira osnovni model AB okvira sa zidanim ispunom od šuplje blok opeke, bez dodatnih veza ispuna i okvira, dok Model #2 reprezentira ojačan model izveden na prethodno ispitanom AB okviru (Model #1), pri čemu je korištena puna opeka u kombinaciji s vertikalnim serklazima. U kratko su prikazani globalni dinamički odzivi, maksimalni međukatni pomaci i usporedba vlastitih frekvencija Modela #1 i #2 kao evaluaciju ojačanja Modela #2 u odnosu na Model #1., Reinforced concrete (RC) frame structures are dominantly used for the construction of low and medium{high structures on the territory of Croatia, and sometimes such structures in seismically active zones need to be strengthened to increase the lateral bearing capacity, stiness and/or ductility of the primary bearing structure. In this dissertation, the use of masonry inlls, with dierent types of connection between the inll and the RC frame, was elaborated as an element for strengthening the basic RC structure for the earthquake action. It is known that the presence of inlls, and without any additional connection with the frame, signicantly changes the dynamic response of the structure, whereby the inll elements can not be neglected in the dynamic or static analysis of the structure. Existing valid regulations do not contain any clarication of the impact of such reinforced structures, which makes this area even more interesting. The present ndings have shown that the uniform presence of masonry inlls contributes to greater stiness and lateral (in-plane) bearing capacity, with the structure experiencing less global displacements, and thus less damage, which is often considered to be positive eects of masonry inlls. On the other hand, the presence of inlls can lead to local or global plastic deformations of the primary frame structure, forming short columns, shear failures of the beam-column joints or forming the so-called soft storey mechanisms, and reduction of the ductility of individual elements and/or structure as a whole, which are certainly one of the negative eects of inlls. By strengthening the frame by adding inlls in combination with mutual interconnection, it is primarily intended to improve the interaction between the inll and the frame, which can be observed also through the contribution of the ductility of the system, and by reducing the possible negative eects of the inll mentioned earlier, on the one-bay, one-storey specimens. The doctoral dissertation deals with the behaviour of bare planar RC frames, as well as the planar RC frames strengthened by the addition of masonry inlls in combination with the mutual interconnection of the inll and the frame elements for the earthquake action. Using the present knowledge of the composite inlled{frame system and their interaction, the primary aim of this dissertation was to explore the possibilities of using the inll walls in RC frames as a strengthening method, observing the in-plane cyclic responses obtained by experimental testing of particular specimens. In order to contribute to understanding the strengthening of the frame by masonry inlls, experimental and numerical researches have been carried out. The experimental part of the study was carried out on 10 one{bay, one-storey specimens of ductile and non-ductile RC frames strengthened with masonry inll (hollow clay block and solid clay bricks units) and 7 related reference specimens used for evaluation of inll strengthening and the quality of the inll and frame mutual interconnection. In addition to the static cyclic test of specimens itself, the mechanical characteristics of the embedded materials were also tested (concrete, reinforcement, wall elements, masonry, mortar and composite materials). Frame specimens are built in scale 1:2.5 for ductile and 1:2 for non-ductile frames, tested at constant vertical and incrementally increased horizontal cyclic load (static reversed-cyclic test). The test specimens can be grouped according to the type of inll element (hollow clay block and solid clay brick units), type of RC frame (ductile and non-ductile), and type of connection between the inll and the frame. This provides a total of 6 diferent strengthening congurations, of which some are applied to two types of inll. By analysing the results of these experimental studies, the characteristics of the behaviour of each specimen were presented, and the most suitable type of strengthening for the ductile and non-ductile frames was determined. For all experimental specimens, of which 10 original and 7 used as references, the same calibration was carried out using nonlinear macro-models in OpenSees (PEER, Berkeley, opensees.berkeley.edu). Numerical models are based on so- called beam-column elements for columns and beams, and specic type of compressive/tensile elements for inll walls, for which satisfactory responses to cyclic responses have been achieved with respect to experiments. The same models were used in the numerical case study for predicting the dynamic response to the application on a real building (Tsukuba, Japan) by Incremental Dynamic Analysis (IDA), where IDA curves, fragility curves, vulnerability curves and loss curves were designed for each type of strengthening separately to evaluate the eciency of a particular strengthening in relation to reference models. Finally, an experimental case study of the spatial FRAMA building, Model #1 and Model #2 (FRAmed-MAsonry Composites for Modelling and Standardization, framed-masonry.com), which was built in scale of 1:2.5 and dynamically tested shaking table at the IZIIS (Institute of Earthquake Engineering and Engineering Seismology, iziis.edu.mk), Skopje, Macedonia. The FRAMA building, Model #1 and #2, have very similar characteristics in geometry, type of inll and strengthening type, as is the case with some original planar experimental specimens from the first part of the research. FRAMA Model #1 represents the reference RC frame with masonry inlls of a hollow clay block, without additional mutual interconnections between the inlls and the frame, while Model #2 represents a strengthened model derived from a previously tested RC frame (Model #1), using a solid clay brick in combination with vertical tie-columns. Global dynamic responses, maximum intermediate drifts, and comparison of fundamental frequency of Model #1 and #2 are shown briefly, as an strengthening evaluation of Model #2 with respect to Model #1.

Performance levels in performance-based design procedures have been described in several ways according to the operational status of the structure or the level of damage sustained up to collapse. The selection of the appropriate drift associated with different levels of damage for the design is significant in terms economy and safety. The identification of drift levels associated with different states of damage remains one of the unresolved issues in the development of performance objectives in performance-based design and assessment procedures. The objective of this study is to develop the approach to establish the drift of masonry infilled frames that is associated with different definable levels of damage to use as performance objectives in the design of new structures and the evaluation of the seismic resistance of existing structures. Analytical and experimental data were used to examine the correlation between drift and damage of masonry infilled frames. The analytical procedure included pushover analyses of various designs of reinforced concrete frames with masonry infills. Seismic response has been analysed, considering Inter-storey Drift Ratio (IDR) as main intensity measure. The experimental results were obtained from Experimental Database of Infilled Frames – EDIF and reviewed for the appropriateness and consistency of the data. As a result, a new relationship among structural performance, damage levels and Inter-storey drift ratios for masonry infilled frames was developed.

Over the last years the seismic behaviour of infilled reinforced concrete (RC) structures have been focus of innumerous experimental and numerical studies. A big effort is being made by the scientific community with the aim of increase the knowledge regarding the seismic response of these type of structures and improve the numerical modelling accuracy to predict their expected behaviour. In 2015, a blind prediction contest was organized by the Faculty of Civil Engineering Osijek with main goal of invite the technical and scientific community to predict the nonlinear seismic behaviour of a 1:2.5 scaled 3D building struc- ture. The three-storey infilled RC structure was subjected to ten incremental earthquake se- quence on a shake table test. The blind numerical analyses were performed knowing only the specimen geometry, reinforcement detailing, material characteristics and the actual ground motions recorded during the testing. In this context and, in view of the author’s participa- tion success, the present paper mainly aims at presenting the key aspects of the adopted nu- merical methodology (and related difficulties) which proved to yield good results, while also providing some insight regarding key problems in numerical simulations of infilled RC structures seismic behaviour.

U radu su prikazani prmjeri različitih urbanističkih i arhitektonskih rješenja gradova budućnosti.

Najveći izazov prilikom modeliranja ovakvih sustava je adekvatno simulirati njegovo ponašanje koje bitno ovisi o interakciji osnovnog okvira i ispuna kao najčešće dviju zasebnih komponenata. U pristupu modeliranju razlikujemo prvenstveno mikro i makro modele. Za ovu studiju usvojen je makro model konstruiran programom OpenSees (Open System for Earthquake Engineering Simulation, PEER, Berkeley) koji ima izvrsne mogućnosti opisivanja globalnog i lokalnog ponašanja sustava, te je u isto vrijeme robustan, fleksibilan i nudi detaljan uvid u prirodu ponašanja uz razuman broj potrebnih parametara za opisivanje modela materijala. Analiza pouzdanosti je provedena na temelju nelinearnog numeričkog modela, na kojem je moguće analizirati statička i dinamička opterećenja. Ovakav pristup ima prednost ponajprije u mogućnosti reduciranja nesigurnosti koje su inače prisutne kod analitičkog definiranja jednadžbe graničnog stanja, čiji se oblik znatno komplicira uzevši u obzir nelinearnost i statičku neodređenost modela. Za procjenu pouzdanosti horizontalne nosivost, u domeni potresnog inženjerstva, dovoljno je definirati jednadžbu graničnog stanja ograničavanjem međukatnog pomaka, što se pokazala najbolja mjera štete konstruktivnih elemenata. Niža razina dokaza pouzdanosti (FORM) koja je operativnija u praksi provodi se s pomoću operativne vrijednosti vjerojatnosti otkazivanja Pf koja se naziva indeks pouzdanosti β i obrnuto je proporcionalna vjerojatnosti otkazivanja Pf. Cilj ovog rada je prvenstveno procijeniti pouzdanost horizontalne nosivost nelinearnog modela statičkom metodom postupnog guranja (engl. static pushover), tako da je provedena FORM analiza i Monte Carlo simulacije metodom konačnih elemenata, te je uspoređena vrijednost vjerojatnosti otkazivanja Pf. Numerički makro model je kalibriran na temelju prethodno provedenim eksperimentima statičkim cikličkim opterećivanjem u ravnini, pri čemu su ispitane i karakteristike sastavnih materijala iz kojih su definirane slučajne varijable za beton, armaturni čelik i ziđe, dok je varijacija razine vertikalnog opterećenja također definirana eksperimentom. Iskazivanje vrijednosti vjerojatnosti otkazivanja Pf putem Monte Carlo simulacije generiranje N slučajnih ishoda izračunava se kao Nf/N pri čemu je nužan veliki broj simulacija, odnosno N ≥ 10^5, za preciznu procjenu pouzdanosti. Numerički model predstavlja armirano–betonski okvir jednog raspona i jedne visine, originalno konstruiran u mjerilu 1:2.5, te se sastoji od linijskih konačnih elemenata za stupove, gredu i pojednostavljene tlačne dijagonale za reprezentaciju zidanog ispuna. Stupovi i greda modelirani su Force–Based elementom s pridruženim Fiber presjekom i definiranom duljinom plastičnih zglobova, dok je zidani ispun modeliran sustavom tlačnih opruga. Horizontalno opterećenje je nanošeno u 20 koraka do 100% iznosa koje je definirano kao maksimalna nosivost temeljem eksperimenta, te se pratio vršni pomak ravnine grede koji je ograničen jednadžbom graničnog stanja, pripadajućim iznosom pomaka pri vršnoj nosivosti. Za najrealnije opisivanje ponašanja konstrukcija u potresnom inženjerstvu nelinearnom dinamičkom analizom daleko su najveći izvor nesigurnosti zapisi ubrzanja temeljnog tla, uz koji nije zanemariv i izvor nesigurnosti povezan s karakteristikama materijala. Rezultati FORM analize su usporedivi s Monte Carlo simulacijama, te je dobivena optimalna kombinacija parametara materijala za dosezanje ciljanog pomaka definiranog jednadžbom graničnog stanja. Ovakav pristup analizi pouzdanosti daje neograničene mogućnosti u području potresnog inženjerstva te cjelokupnu implementaciju nesigurnosti unutar jednog modela, što je neophodno za procjenu rizika od kolapsa ili procjenu gubitaka unutar okvira PEER PBEE metodologije.

Reinforced concrete frame buildings with masonry infill walls are being widely used in seismic prone regions in Southern Europe. For seismic design and evaluation of existing buildings, the contribution of infill walls is usually neglected although it can be and usually is beneficial. Its contribution is of special importance for seismic strengthening of RC frame buildings, where it can be of special importance. Strengthening methods are not sufficiently investigated, especially experimentally, and the investigation of these is necessary. Within the scope of our research, we have planned to investigate possible strengthening methods, of strong and weak frames, by application of the masonry infill. Reinforced concrete frame was designed according to the EC8 and for masonry infill we used hollow and solid clay masonry units. One storey- one bay specimens, built in a scale 1:2.5, were tested under constant vertical and cyclic in-plane lateral loads. In the full paper, we will present only one part of the experiments that were performed at the Laboratory for experimental mechanics at the Faculty of Civil Engineering in Osijek, Croatia.

Sustav armiranobetonskih okvira s zidanim ispunom, uokvireno ziđe, uobičajen je kompozitni konstruktivni sustav za prijenos opterećenja kod niskih i srednje visokih građevina i čest je u područjima srednje i visoke seizmičnosti. On najčešće nije projektiran kao jedinstven nosivi sustav, te spoznaje o ponašanju pri djelovanju potresa nisu pratile ekspanziju njegove primjene. Ponašanje komponenti sustava (okvir i ispuna) pri djelovanju horizontalnih sila, bitno se razlikuje od ponašanja samog sustava. Pri tome njihova međusobna interakcija ima presudan utjecaj na nosivost i način sloma sustava. Okviri su fleksibilniji i duktilniji od zidanog ispuna. Uobičajena je njihova podjela na „jake“ okvire projektirane sukladno seizmičkim propisima i „slabe“ okvire koji su projektirani u sustavu neduktilnih armirano-betonskih okvira ili kontinuiranih greda na stupovima bez okvirnog djelovanja između stupova i greda. Zidani ispun doprinosi krutosti i nosivosti okvira, ali je izrazito heterogen, nelinearan i krt materijal. Kombinacijom svojstava okvira i ispuna dobiva se sustav uokvirenog ziđa koji, uz poznavanja ponašanja, može biti pouzdan za preuzimanje horizontalnih opterećenja te za ojačanje postojećih „slabih“ okvira. U okviru znanstveno- istraživačkog projekta “Seizmičko projektiranje okvira s ispunom” kojeg je financiralo MZOS Republike Hrvatske pod brojem 149-1492966-1536 istraživano je ponašanje ovakovih sustava. Na osnovi vlastitih eksperimentalnih i numeričkih istraživanja uočene su razlike u ponašanju jakih i slabih okvira pri seizmičkom djelovanju, mogućnosti i svojstva ojačanja okvira te su predložene metode proračuna jedinstvenog sustava uokvirenog ziđa.

Priručnik interne namjene prikazuje i objašnjava napredne opcije korištenja potresnog stola Quanser Shake Table II (izvorno razvijen za sveu čili šte University Consortium on Instructional Shake Tables (UCIST)). Ovakav instrument mo že se koristiti za podučavanje u podru čju dinamike konstrukcija, u pogledu izolacije vibracija, kontrole odziva, te u ostalim podru čjima tehni čke mehanike i građevinarstva. U priručniku su objašnjene i dane upute za upravljanje potresnim stolom putem MATLAB-a i SIMULINK-a. Upravljanje potresnim stolom podrazumjeva u čitavanje i modificiranje željenih potresnih zapisa iz bilo kojih svjetskih baza i formata, korištenje "Sine- sweep" i "Sine" funkcija uz otključavanje tvorničkih ograničenja seizmičke pobude u pogledu frekvencije, te obrada rezultata sa izvornim algoritmima (skriptama) napisane u MATLAB kodu od strane autora.

As part of a broader research project, attention of this study has been focused on the existing, damaged “strong frame“ RC buildings and “weak frame“ RC buildings, strengthened with clay brick masonry infill walls (“framed‒ wall”). We experimentally investigated different masonry wall application techniques within the frame that upgrade the seismic capacity of these structures. Seven one‒bay, one‒storey RC frames were built in a scale 1:2.5 and 1:2, “strong“ and “weak” frames respectively. They were tested under constant vertical and reversed cyclic lateral loading up to the drift of 1.5%. The experimental results are presented in the form of observed failure mechanism, hysteresis loops and cyclic envelope curves. The tests showed that RC frames strengthened with masonry infill wall had the improved lateral load and deformation capacity as well as energy dissipation. The system behaved as composite “framed‒masonry” structure which damage could be controlled. Cost‒ effectiveness and simplicity of the technique by the implementation of the masonry infill wall seems to be much more favourable than just the repair of the existing RC bare structure.

Navedena studija temelji se na procjeni seizmičke oštetljivosti duktilnih ravninskih armirano–betonskih okvirnih konstrukcija sa različitim konfiguracijama zidanog ispuna, koristeći inkrementalno dinamičku analizu (IDA) na nelinearnim numeričkim modelima zgrada. Kroz probabilističku analizu istražena je i uspoređena seizmička oštetljivost za tri različita modela armirano–betonske okvirne konstrukcije sa zidovima ispuna, korištene kao prototip u znanstvenom projektu i eksperimentalnom istraživanju, modelirane kao ravninski okvir sa različitim rasporedom ispuna po visini. Ocjena ponašanja i oštetljivosti se zasniva na modelima dimenzioniranim prema normama Eurocode.Studija kvantificira utjecaj prisutnosti i konfiguracije zidanog ispuna na seizmički rizik od kolapsa ili urušavanja, empirijskim pristupom, putem inkrementalno dinamičke analize kao dio referentnog okvira seizmičkog proračuna i potresnog inženjerstva sukladno očekivanom odzivu (engl. PBEE). Kao konačni rezultat konstruirane su krivulje oštetljivosti (engl. Fragility curves) koje prikazuju vjerojatnosti otkazivanja ili razine oštećenja za definirana granična stanja oštetljivosti (engl. Limit states). Čisti armirano–betonski okvir pokazao je da ima veću vjerojatnost oštećenja što je u korelaciji sa većim međukatnim pomacima, dok je shodno tome potpuno ispunjen okvir po visini imao najmanju vjerojatnost dosezanja određenog graničnog stanja. Takopotpuno ispunjen okvir ima najnižu razinu rizika od kolapsa ili otkazivanja, dok je čisti AB okvir najranjiviji na potresom inducirani kolaps.

Seismic fragility assessment of masonry infilled reinforced‒concrete frames was analysed. Three model structures with different infill configurations, were used. Developed and interpreted were the probabilistic fragility curves using Incremental Dynamic Analysis (IDA) and a set of seven earthquake records was used. Influence and contribution of infill walls to the system behaviour was evaluated. Results are presented as median values of the fragility curve for four limit states corresponding to the damage scale and damage measure of interest (Inter‒storey Drift Ratio, IDR). It could be concluded that fully‒infilled frame had 50% lower values of maximum Inter‒storey Drifts and had probability to survive up to 3 times higher intensities of spectral acceleration in regard to the bare frame.

The aim of the project was to introduce the participants into advanced requests in the field of earthquake engineering. The studies were concentrated on a template design RC school building (Figure 1), which revealed low seismic resistant in the past earthquakes in Turkey. Therefore the Turkish Government started after the damaging events in 1999 a campaign to investigate and strengthen these buildings all over Turkey. In the frame of these campaign one typical school building, with quite similar ground plans to the school building which failed during the Bingöl Earthquake in 2003 could be instrumentally investigated before and after strengthening. The participants of the project assessed the performance of the structure before and after the applied strengthening measures on the basis of measured building response data and evaluate the earthquake resistant design. They carried out damage prognosis for the given seismic action and compared it with the real occurred damage after the Bingöl EQ by using modern software tools.

Reinforced concrete frame buildings with masonry infill walls are being widely used in seismic prone regions in Southern Europe. For seismic design and evaluation of existing buildings, the contribution of infill walls is usually neglected although it can be and usually is beneficial. Its contribution is of special importance for seismic strengthening of r/c frame buildings, where it can be of special importance. Strengthening methods are not sufficiently investigated, especially experimentally, and the investigation of these is necessary. Within the scope of our research, we have planned to investigate possible strengthening methods, of strong and weak frames, by application of the masonry infill. Up to now, following strengthening methods of the strong r/c frame, were investigated: a) Masonry infill anchored to the surrounding r/c frame, b) Reinforced masonry infill anchored to the surrounding r/c frame and c) Masonry infill wall with additional confining element. Reinforced concrete frame was designed according to the EC8 and for masonry infill we used hollow and solid clay masonry units. One story- one bay specimens, built in a scale 1:2.5, were tested under constant vertical and cyclic in-plane lateral loads. Tests were performed at the Laboratory for experimental mechanics at the Faculty of Civil Engineering in Osijek, Croatia. The test details and experimental results will be presented at the Bauhaus Summer School in Weimar 2012. Specimen details and applied strengthening methods are presented. The results of strengthened specimens, are compared to the previous experiments when the r/c frame was without infill and with infill with no connection to the frames.

This study assesses the seismic vulnerability of ductile reinforced concrete frames with masonry infill walls, utilizing nonlinear dynamic analysis of building models. The evaluation is based on structures designed and detailed according to Eurocodes. The research quantifies the effect of presence and configuration of masonry infill walls on the seismic collapse risk using Incremental Dynamic Analysis within the performance-based framework. Seismic vulnerability assessment indicated that of the configurations considered (bare, partially-infilled and fully-infilled frames), the fully-infilled frame had the lowest collapse risk and the bare frame is found to be the most vulnerable to earthquake-induced collapse. The study compares seismic vulnerability of reinforced-concrete frame structures with- and without infill. An Incremental Nonlinear Dynamic Analysis of the model planar reinforced-concrete frames exposed to a set of recorded ground motions was performed in order to evaluate their seismic vulnerability.

Okviri s ispunom su kompozitne konstrukcije koje se sastoje od armiranobetonkih okvira i ispune za koju se u Hrvatskoj uobičajeno rabe blok opeke ili čak i betonski blokovi. Ispuna bitno mijenja odgovor konstrukcije na potres i njen se utjecaj mora na odgovarajući način uzeti u proračun. Polazeći od problematike modeliranja zidanih ispuna u a-b okvirima uslijed djelovanja seizmičkih sila, i njenom razradom dolazimo i do metoda ojačanja istih. Time se, uz isti nepromjenjeni okvir, želi postići veća horizontalna nosivost i duktilnost ispune, od koje se nadalje očekuje što veća deformabilnost, odnosno interaktivnost ispune s okvirom te disipacija određenog dijela seizmičkih sila.

Idejno rješenje grednog mosta za prijelaz suhe prepreke širine 16 metara. Most ulazi u kategoriju cestovnih mostova. Projekt po poglavljima: analiza opterećenja, razdioba opterećenja na glavne nosače, dimenzioniranje glavnih nosača, ploča i konzola, proračun za plan armature rasponskoga sklopa, proračun sidrenja i preklopa armature, proračun sila za ležaj, dimenzioniranje ležaja, proračun prijelazne naprave sa promjenom temperature, skupljanjem, puzanjem i silom kočenja.

Identična okvirna armiranobetonska konstrukcija (katnost, tloris, stalno i promjenjivo djelovanje) dimenzionirana u skladu s EN 1998:2004 u području seizmičkog intenziteta IX na dva načina: s ograničeno duktilnim ponašanjem i s najvećim mogućim duktilnim ponašanjem. Utvrđene su kvalitativne i kvantitativne razlike koje su rezultat različitog pristupa seizmičkom proračunu.

Projektno-tehnička dokumentacija armiranobetonske konstrukcije iznad pet željezničkih kolosjeka i perona željezničke postaje ukupne duljine 75 m između ležajeva na rubnim upornjacima. Rad kroz faze idejnog, glavnog i izvedbenog projekta sadrži slijedeća poglavlja: odabir konstruktivne koncepcije, razrada konstruktivnih elemenata, argumentirani odabir njihovih dimenzija, analiza prijenosa opterećenja na vertikalne ležajne konstruktivne elemente koji se ne dimenzioniraju u ovom radu, tehnički opis konstukcije, plan pozicija konstrukcije, statički proračun, dimenzioniranje konstrukcijskih elemenata, detaljan arhitektonski nacrt, nacrt konstrukcije, nacrti (planovi) armature s iskazom količina, perspektivni 3D prikaz konstrukcije.