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In light of the forthcoming second generation Eurocodes (EC), the results of conducted systematic in-plane cyclic and compressive tests on three-leaf stone masonry walls are discussed following new requirements and provisions. The new proposal for EC8-3 for existing buildings is based on partial factors safety approach, though it considers different uncertainties in defining input parameters for effective seismic performance-based assessment. Prior to its application, massive calibration effort will be needed since there is no standardized method for shear testing of masonry walls. In this paper, the performance limit states damage, resistance, and displacement capacities from conducted test results were evaluated and assessed through comparison with analytical solutions and imposed limit values, as stated in existing codes. The test results provide a much higher deformation capacity than the limits provided in both existing and new proposal of EC8-3 as well as those in the ASCE code provisions. The reason for this lies in the soft, "ductile" mortar for which the presumed resistance according to code provisions should be significantly higher when considering good quality ashlar three-leaf stone masonry.

There is a lack of knowledge regarding the parameters needed for the effective seismic performance assessment of historical stone masonry buildings. The paper presents the results of an extensive experimental campaign consisting of four compression and fifteen in-plane cyclic shear tests on three-leaf ashlar stone masonry walls and its constituents. The morphology, level of vertical load, and testing boundary conditions were systematically varied, and their influence on the load-bearing and deformation capacities, stiffness, ductility and energy dissipation was analysed. Good consolidation of the inner core enables in-plane failure mechanism of the walls to occur without decisive out-of-plane damage. The boundary conditions applied significantly influence the failure modes and large deformation capacities obtained, whereas transverse connections in the case of a shear failure mechanism do not significantly influence the overall lateral in-plane response of walls.

V prispevku so opisane preiskave troslojnih kamnitih zidov, namenjene študiju njihovega obnašanja pri potresnih obremenitvah. Preiskave so obsegale tlačne in strižne teste skupaj 18 zidov ter spremljajoče raziskave konstituentov (malte in kamna). Analizirani so rezultati maksimalnih nosilnosti kot tudi pomikov ter poškodovanosti zidov za karakteristična stanja obnašanja pri tlačnih in strižnih obremenitvah. Pri strižnih preiskavah je analiziran tudi vpliv morfologije zidov (sestave po prerezu), različnih nivojev predkompresije in robnih pogojev vpetja. Preizkušani tip kamnitih zidov najdemo v Sloveniji v starejših reprezentativnih objektih (na Primorskem ali tam, kjer je bil pri gradnji prisoten italijanski oziroma beneški vpliv), ti pa predstavljajo pomemben del naše kulturne dediščine. Pri takšnih objektih je poleg konstrukcije pogosto v interesu ščititi različne poslikave, mozaike itd., zato je bil na zidove nanesen tudi apneni omet, ki je služil za analizo obnašanja umetnostnih elementov zidov in določitev vrednosti mejnih zasukov zidov za nadaljnjo uporabo pri oceni potresne odpornosti obstoječih objektov tudi s stališča poškodovanosti ometov.

Injektiranje je jedan od najdjelotvornijih, a često i najprikladnijih postupaka za pojačanje zidova starih zidanih građevina. Da bi se ocijenio utjecaj raznih vrsta injekcijskih smjesa na mehanička svojstva zidanih građevina, obavljeno je ispitivanje in situ postojeće zidane građevine. Dobiveni rezultati korišteni su za ocjenu seizmičke otpornosti građevine pomoću metode postupnog guranja, uz primjenu pristupa katnog mehanizma i mehanizma globalnog odziva. Prihvatljivije vrste injekcijskih smjesa usporedive su s cementnim injekcijskim smjesama. Dobiveno je da se pristupom globalnog odziva postižu realniji rezultati čak i kod niskih zidanih građevina

U radu je opisana usporedba laboratorijskih i terenskih ispitivanja na posmik zidova ojačanih karbonskim (C) trakama i staklenim (G) mrežicama u polimerima s rezultatima proračunskih modela za zidove s FRP-om. Rezultati ispitivanja na zidovima od nove i stare pune opeke pokazali su povećanje posmične nosivosti i graničnog pomaka - najviše za horizontalne i horizontalno-vertikalne epoksidom zalijepljene trake te mrežice u modificiranom cementnom mortu, a najmanje za dijagonalne trake zbog odstupanja sa zida. ACI i CNR računski modeli pokazali su najbolje podudaranje s eksperimentima.

Structural analysis of historical constructions : proceedings of the [8th] International Conference on Structural Analysis of Historical Constructions

Comparison of in-situ and laboratory tests of brick masonry walls strengthened with carbon fibre reinforced polymer fabric

Design of lateral resistance of URM blockwork through theoretical models and code provisions

Optimization of contemporary blockwork masonry for seismic regions - step by step approach

Water absorption of lime-based facades

V magistrski nalogi je izdelana nelinearna seizmična analiza po predlogu delovne različice novega Evrokoda 8 na primeru zahtevnejše starejše zidane stavbe - palače. V prvem delu naloge so predstavljene spremembe pri preverjanju potresne odpornosti obstoječih zidanih stavb, ki se nanašajo na nosilnost zidov, deformacijsko kapaciteto zidov in izvedbo nelinearne analize. Temu sledi opis konstrukcije obravnavane stavbe, nabor materialnih karakteristik, nabor vplivov in opis modeliranja konstrukcije. Podani so predlogi utrditvenih ukrepov za izboljšanje obnašanja konstrukcij med potresnim delovanjem. Vpliv potresne obtežbe modeliramo z upoštevanjem Evrokodovega elastičnega spektra. Opisu modeliranja tako sledi opis načina definicije spektrov pospeškov po novi delovni različici Evrokoda. Z upoštevanjem zahtev obstoječe različice Evrokoda in delovne različice novega standarda izvedemo potisno analizo in s pomočjo metode N2 ocenimo njeno potresno odpornost. Najprej je opravljena analiza objekta v obstoječem stanju, čemur sledi analiza treh ojačitvenih variant. V zaključku primerjamo razlike med trenutno veljavnim standardom in novo delovno različico Evrokoda. Temu sledi primerjava rezultatov analize po obeh različicah standarda. In the master's thesis, a non-linear seismic analysis was made according to the proposal of the draft version of the new Eurocode 8 on the case study of cultural heritage brick building - palace. In the first part of the thesis, changes in the verification of the seismic resistance of the existing brick buildings were presented. The changes related to the load-bearing capacity of the walls, the deformation capacity of the walls, and the performance of non-linear analysis. This was followed by a description of the structure of the analysed building, defining material characteristics, defining influences, and a description of the modelling of the structure. Proposals for different strengthening measures were given to improve the behaviour of structures during seismic action. The influence of seismic loading was modelled by considering the Eurocode elastic spectrum. Following the modelling description a description of the acceleration spectra as defined according to the new working version of the Eurocode was presented. Considering the requirements of the existing version of the Eurocode and the draft version of the new standard, we have performed a push-over analysis and evaluated its seismic resistance using the N2 method. Firstly, an analysis of the building in its existing state was carried out. It was then followed by an analysis of three strengthening options. In conclusion, we have compared the differences between the currently valid standard and the new draft version of the Eurocode. This was followed by a comparison of the results of the analysis according to both versions of the standard.

Obravnavana vila blok stavba je bila naključno izbrana in je locirana na Beljaški ulici v Ljubljani. Narejena je v AB izvedbi. Njeni gabariti so uporabljeni za definicijo izhodiščnega modela zidane stavbe. Na podlagi tega modela izhajajo vsi različni primeri modelov, ki se razlikujejo v odvisnosti od pripisanih parametrov. Parametri v analizi variirajo po številu etaž, tipu zidane konstrukcije, tlačni trdnosti malte, karakterističnem koeficientu trenja in materialnemu varnostnemu faktorju. Pripravljeni modeli so obremenjeni z lastno težo, koristno obtežbo, obtežbo snega in potresno obtežbo. Z določenimi geometrijskimi podatki zidov, njihovimi mehanskimi lastnostmi in pripadajočimi vplivi, se preveri nosilnost vsakega posameznega zidu. Na podlagi zadostne nosilnosti vseh zidov za določen model se lahko oceni globalna nosilnost celotne konstrukcije. Opravljene kontrole za nosilnost zidov so znotraj linearne elastične teorije povzete iz standarda Evrokod. Z novim predlogom standarda Evrokod prihajajo dodatne nove kontrole, ki so v tej analizi opravljene za primerjavo z obstoječimi. V rezultatih in zaključku diplomske naloge so zapisane ugotovitve, ki nam jih je prinesla parametrična študija. The analysed villa block building, that was randomly chosen is located on Beljaška ulica in Ljubljana. It is made from reinforced concrete elements. Its dimensions are used as the base of the initial model of the masonry building. All other models that were used in this parametric study were derived from this building. They diverge in dependence from the assigned parameters. The parameters in the analysis that were varies are number of storeys, the type of masonry structure, the compressive strength of masonry mortar, the characteristic friction coefficient and the material partial safety factor. Load cases that were considered were dead load, imposed load, snow load and seismic load. The load-bearing capacity of each individual wall is checked in respect to its geometrical data, mechanical properties and the associated load. Based on the sufficient load-bearing capacity of all walls for a given model, the global load-bearing capacity of the entire structure in elastic state can be estimated. The performed controls for the assessment of load-bearing capacity of the walls are within the linear elastic theory summarized from the Eurocode standard. With the new proposition of the next generation of Eurocodes come additional new controls, which are in this analysis compared with the already existing ones. The findings brought to us by this parametric study are summarized in the conclusion of the diploma thesis.

V sodobni arhitekturi so vedno večje zahteve po transparentnosti fasadnega stavbnega ovoja. Unikaten in najbolj primeren material kateri nam to omogoča je steklo. V primeru, da so stekleni elementi tudi v funkciji konstrukcijskega materiala, jim je potrebno zagotoviti ustrezno nosilnost, togost in obstojnost. Izboljšanje mehanskih lastnosti lahko dosežemo s toplotno obdelavo oziroma kaljenjem stekla, večjo varnost po porušitvi pa z lepljenjem steklenih šip med seboj. Tako obdelano in lamelirano steklo imenujemo konstrukcijsko steklo. Ker je tovrstno steklo kot element stavbnega ovoja izpostavljeno različnim vremenskim razmeram, so pomembne lastnosti stekla ter vmesnega povezovalnega sloja, ki je bil uporabljen v postopku lameliranja. Izpostavljenost lameliranega stekla vlažnim pogojem okolja lahko povzroči delaminacijo, prav tako lahko UV žarki povzročijo obarvanje in propadanje vmesnega povezovalnega sloja. Velik vpliv na togost in nosilnost lameliranega stekla ima temperatura. Pri neposredni izpostavljenosti sončnim žarkom se steklo in polimerni material med šipami segrejeta kar povzroči, da se polimernemu materialu spremeni viskoznost. V sklopu diplomske naloge smo preizkušali vpliv povišane temperature na obnašanje lameliranega konstrukcijskega stekla. Meritve smo izvajali na dveh vrstah preizkušancev v temperaturni komori pri povišanih temperaturah. Prvi so imeli za vmesni sloj EVA, drugi pa PVB folijo. Vse preizkušance smo obremenjevali s konstantno hitrostjo in opazovali njihov odziv pri tritočkovnem upogibu. Merili smo poves na sredini preizkušanca, deformacije na natezni strani na sredini razpona preizkušanca in strižni zdrs med steklenima paneloma. Rezultati so pokazali, da so preizkušanci z EVA vmesnem sloju že pri sobni temperaturi bolj togi v primerjavi s preizkušanci kateri so imeli PVB vmesno povezovalno plast. Vse vrednosti deformacij, pomikov in zdrsov pa so se pričakovano pri obeh vrstah preizkušancev povečevale z višanjem temperature, zaradi spremembe viskoznosti vmesne povezovalne plasti in s tem znižanja njenega strižnega modula. One of the common requirements in modern architecture is the transparency of building envelope and its structural elements. The material which can provide this at very high aesthetic level beside load bearing capacity, stiffness and durability is glass. The enhancement of glass can be achieved with tempering of glass plates and with gluing them together into laminate with the polymer interlayers. This type of glass can be named structural glass and it can be in real application exposed to atmospheric conditions which can dramatically influence the short or long term behaviour of laminated glass. Under external atmospheric conditions the laminated glass become prone to delamination and UV degradation of interlayer. The essential influence on laminated glass stiffness has temperature due to the changed viscosity of polymeric interlayer. Within this thesis the influence of elevated temperature on the behaviour of laminated glass was investigated. We conducted the three point bending test in the environmental chamber under elevated temperature for two types of laminated glass, one with EVA and the other with PVB interlayer. All specimens were loaded with the constant load rate. During the experiment conduction we observed and measured the midspan deflection, longitudinal tension deformation at the bottom glass sheet and shear deformation between the glass sheets. The results show that the specimens with EVA interlayer have higher stiffness at room temperature comparing to those with PVB interlayer. Based on the measured values and results at elevated temperatures we can confirm and conclude that both types of specimens lost the initial stiffness because of viscosity change of interlayer and thus lower shear modulus.