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Vlepljene palice predstavljajo zanimivo rešitev stikovanja nosilnih lesenih elementov, s številnimi ugodnimi lastnostmi kot so visoka nosilnost, dobra požarna odpornost, prilagodljivost z arhitekturnega vidika, idr. Kljub številnim prednostim, je uporaba vlepljenih palic v praksi relativno omejena. Uporablja se le v posebnih primerih za stikovanje masivnega ali lepljenega lesa. V prispevku je podrobno predstavljena možnost uporabe vlepljenih palic za stikovanje panelov iz križno lepljenega lesa (angl. Cross Laminated Timber, krajše CLT). Stikovanje CLT elementov z vlepljenimi palicami je še razmeroma neraziskano in se v praksi še ne uporablja. V raziskavi je bilo izvedenih 60 preskusov, pri čemer se je preizkusilo različne sidrne dolžine vlepljenih palic (80 do 400 mm), premere palic (16 do 24 mm) ter položaje palice glede na smer lesnih vlaken (vzporedno in pravokotno). Preskusi so pokazali različne porušne mehanizme in drugačen odziv kot pri primerljivih spojih vlepljenih palic v masivnem in klasičnem lepljenem lameliranem lesu (t.j. zdrs med sloji CLT), kar lahko pomeni, da ima spoj tudi bistveno nižjo nosilnost.

At the end of August 2016 an earthquake with a magnitude of 6.2 Mw hit Central Italy, followed by many strong aftershocks, which caused nearly 300 casualties and extensive damage. Less than two months later we had the opportunity to visit part of the affected area and see the seismic damage live. The majority of the affected buildings, seen in the field, were stone masonry buildings; there were almost no modern buildings in the area. Almost all of the buildings in the affected villages, which belong to the region Arquata del Tronto, are more or less damaged, while the village Pescara del Tronto is almost completely ruined. The damage observed is typical for stone and poorly connected buildings, dominated by shear damage. It turned out that buildings with r.c. columns behaved better than those without them. The article presents the earthquake data, typical earthquake damage of brick buildings, damage of two skeletal reinforced concrete structures and shows possible methods for interventional supporting of strongly damaged buildings. Konec avgusta 2016 je osrednjo Italijo prizadel potres z magnitudo 6,2 Mw in več močnimi popotresnimi sunki; povzročil je skoraj 300 žrtev in večjo gmotno škodo. Slaba dva meseca po potresu smo dobili priložnost, da obiščemo del prizadetega območja in si poškodbe ogledamo v živo. Glavnina prizadetih stavb je bila kamnitih zidanih, sodobnih stavb je bilo na obiskanem območju zanemarljivo malo. V prizadetih vaseh, ki sestavljajo naselje Arquata del Tronto, so skoraj vse starejše stavbe tako ali drugače poškodovane, vas Pescara del Tronto pa je skoraj v celoti uničena. Poškodbe so tipične za kamnite in slabo povezane stavbe, prevladujejo strižne poškodbe; stavbe z vezmi so se obnašale bolje kot tiste brez. V prispevku so podatki o potresu, predstavitev tipičnih poškodb zidanih stavb, poškodbe dveh skeletnih armiranobetonskih konstrukcij in prikaz načinov interventnega popotresnega opiranja močno poškodovanih stavb.

The paper presents an experimental study of seismic resistance of reinforced concrete columns for the purpose of analysing the influence of uncertainty of material characteristics and uncertainty in manufacture. In order to cover all of the considered sources of uncertainty, 12 columns were manufactured in three different companies. The same plan and nominally the same materials were used in the production of the columns. In addition to the material characteristics, the influence of lapping of longitudinal reinforcement on the seismic response of columns was analysed as well. The columns were tested with cyclic horizontal load, which was increased until collapse. The research has shown that there are big differences in the manufacture of the columns, which is observed in the seismic response after reaching the maximum capacity. The biggest influence on the ductility can be attributed to the detailing of the stirrups. The research has also confirmed some already well-known dependences and demonstrated that one of important parameters of the seismic resistance of columns might be the location of the first stirrup above the foundation. V članku so prikazane eksperimentalne preiskave potresne odpornosti armiranobetonskih stebrov, ki so bile opravljene na Zavodu za gradbeništvo Slovenije (ZAG) z namenom, da se določi vpliv negotovosti oz. razpršenosti materialnih karakteristik in izvedbe na potresni odziv stebrov. Da bi zajeli kar se da veliko virov negotovosti, smo naročili izdelavo 12 stebrov, ki so jih izdelala tri različna podjetja na podlagi istega načrta in nominalno enakih materialov. Poleg materialnih karakteristik smo analizirali vpliv preklopa vzdolžne armature na potresni odziv stebrov. Stebre smo preizkusili s ciklično horizontalno obtežbo, ki smo jo povečevali do porušitve. Raziskave so pokazale, da so med proizvajalci v resnici velike razlike, ki pa so opazne predvsem pri odzivu stebrov po doseženi največji nosilnosti. Največji vpliv na duktilnost ima izvedba armaturnega detajla stremen. Z raziskavo smo potrdili tudi nekatere že znane odvisnosti in opazili, da bi lahko bil pomemben parameter potresne odpornosti tudi lokacija prvega stremena nad temeljem.

V diplomskem delu smo razvijali model za pomoč pri odločanju o izbiri nastopajočih v okviru festivala Teden mladih. Za razvoj modela smo se odločili, ker se nam zdi obstoječi način izbire neprimeren in bi na ta način izboljšali kakovost izbire. Najprej smo določili kriterije, pomembne za izbiro, kar je ena izmed ključnih faz, saj nepopolna izbira kriterijev močno vpliva na končne rezultate. Nato smo določili še zaloge vrednosti in funkcije koristnosti. Razvoj modela je potekal v progamu DEXi, ki nam poda prve rezultate vrednotenja. Za podrobnejšo analizo rezultatov pa smo uporabili še program Vredana, ki nam rezultate razvrsti tudi kvantitativno. Za vrednotenje, ki je najboljši način za preverjanje modela, smo izbrali deset prijav na razpis festivala Teden mladih 2010. Končni rezultat vrednotenja so ocene kandidatov, ki komisiji podajo potrebne informacije, na podlagi katerih lahko izberejo nastopajoče na festivalu. In this diploma, we were developing a model designed for assistance with choosing the ones who will make their appearance on the festival Teden mladih (“Week of the Youth”). We decided to develop the model because we find the existing procedure of choosing inadequate and would like to improve its quality. In the first place, we established the criteria relevant for our choosing, and at here we have to mention that this is one of the crucial phases, since an incomplete set of such criteria may strongly affect the final results. Then we determined the range of usual principal value and the utility functions. The model developing was being executed in the programme DEXi which also provided us with the first results of the evaluation. To acquire a more detailed analysis of the results we used the programme Verdana which sorted the results following the quantitative criteria. Ten applications for appearance on the festival in 2010 were chosen for our evaluation process which is the best way of testing the model. The final result of the diploma writing are grades attributed to candidates who have furnished the necessary information to the commission, the latter being in charge of choosing, on the basis of the obtained information, those who will make their appearance on the festival.

Montažne hale su čest konstruktivni sistem u europskom prostoru za skladišta, poljoprivredne građevine i trgovine. Većina ih se proizvodi industrijskom pre-fabrikacijom te se montiraju na gradilištu. Obzirom na problem veza i malu statičku neodređenost eventualni jaki potres prouzročio bi neposredne i posredne štete što je vidljivo i na primjeru hala iz Turske. Rušenja montažnih hala lako mogu izazvati katastrofalne posljedice naročito u velikim trgovačkim centrima gdje se ovakve konstrukcije često koriste. Za utvrđivanje potresne nosivosti i povredivosti neophodno je poznavanje realnih podataka o nosivosti i ponašanju ovakvih sistema. Ponašanje ovakvih konstruktivnih sistema pri djelovanju potresa još nije dovoljno istraženo, iako se oni doimaju jednostavni i iako su jako često zastupljeni. Malo znanja na tom području se očituje i u propisima za građenje u seizmičkim područjima. U raznim verzijama Eurokoda 8 se nalaze bitno različiti zahtjevi za projektiranje montažnih konstruktivnih sistema. Razlike se očituju kroz različite predložene faktore redukcije potresnih sila, a što je temeljni podatak za projektiranje uz primjenu ekvivalentnog statičkog postupka. Iz ovoga je očito da nedostaje znanja o stvarnom nelinearnom ponašanju montažnih elemenata i njihovih spojeva. Dio tih nepoznanica je istražen u okviru ove disertacije za jedan čest konstruktivni sistem montažnih hala sačinjenih od niza konzolnih stupova povezanih s gredama i pločama. Zahvaljujući stečenim znanjima postalo je moguće istražiti potresnu povredivost takovih sistema i procijeniti potresnu opasnost ne samo za pojedinačne objekte nego i za cijele industrijske zone u pojedinim mjestima. Modeliranje nelinearnoga odgovora izučavanih industrijskih hala je posebno zahtjevno iz dva razloga: 1. Složeno ponašanje spojeva. Disertacija je istraživala ponašanje sistema sa jakim spojevima, koji su bili predimenzionirani u odnosu na elemente konstrukcije te su se plastične deformacije koncentrirale u stupovima. 2. Složeno ponašanje stupova s velikim posmičnim rasponom. Ovaj problem do sada nije bio detaljnije istraživan i njemu je posvećen dio disertacije. Glavni ciljevi disertacije su:  Stjecanje novih znanja na području potresnog odgovora montažnih armirano-betonskih hala ;  Razviti računske modele za armiranobetonske montažne hale, a prvenstveno upotpuniti računske modele za stupove, što omogućuje modeliranje rušenja ;  Odabrati primjereno probabilističku metodu za ocjenu potresne opasnosti za armiranobetonske montažne hale ;  Odrediti potresnu povredivost i opasnost za što veći broj uobičajenih tipova armirano-betonskih industrijskih montažnih hala ;  Ocijeniti i po mogućnosti poboljšati postojeće standarde na području montažnih konstrukcijskih sistema.

The paper explores the possibility of using flexible adhesives to dissipate energy in CLT buildings during earthquakes. In the first series of tests, a rod glued in a CLT panel with flexible adhesive was investigated. The connection was tested in pull-pull configuration using cyclic, tension-only loading. Different rod diameters and different thicknesses of the glue layer were tested. The tests have shown that the adhesive can resist large deformations and exhibits fairly large energy dissipation capacity. Based on the test results the numerical analyses were performed to test the behaviour of the connection when applied in CLT buildings. Existing constitutive models available in OpenSees software were used to simulate the specific hysteretic behaviour of the connection. The results have shown that the CLT wall anchored with “flexible” glued-in rods would have a significant energy dissipation capacity if a sufficient number of them were used as the hold-down devices. Such system could be used to dissipate energy in seismic areas.

Seismic shear magnification in the columns of multi-storey precast structures entering far into inelastic domain is addressed in the paper. Such structures consist of an assemblage of cantilever columns connected with ties. Considering analogy with cantilever walls, it has been expected that during inelastic response the actual shear forces in multi-storey cantilever columns could be considerably higher than the forces foreseen by traditional equivalent elastic analytical procedures (equivalent lateral force or modal spectrum).\ud A parametric study of a set of realistic three-storey structures/columns was performed. These structures were designed according to Eurocodes and shear forces were determined by the equivalent elastic (modal spectrum) analysis. Average values of the shear forces obtained by the inelastic response analysis were compared to those of the traditional (modal spectrum) procedure. They were also compared to magnified shear forces predicted using the shear magnification factor ε suggested in Eurocode 8 for RC ductile walls. In parallel, modelling issues related to the inelastic response analysis of multi-storey cantilever columns were also discussed. Very large seismic force magnifications (up to 3 times and more) were observed. Therefore it is essential to account for this phenomenon in the seismic (capacity) design of cantilever columns in multi-storey precast buildings. It was demonstrated that for this purpose the expression given in Eurocode 8 to account for seismic shear magnification in ductile cantilever walls could be used with some minor modifications.