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V magistrskem delu so predstavljene spremembe pri potresnoodpornem projektiranju konstrukcij, ki jih uvaja predlog novega standarda Evrokod 8. Novosti smo analizirali na praktičnem primeru 5-etažnega jeklenega objekta iz momentih okvirov in okvirov z ekscentričnimi povezji. Preučili smo nove definicije razredov duktilnosti, faktorjev obnašanja, faktorja občutljivosti za stavbe in kontrolo vplivov teorije drugega reda, kontrole etažnih pomikov v novih mejnih stanjih ter pravila za projektiranje jeklenih konstrukcij. Pravila iz trenutnega standarda Evrokod 8 za razred duktilnosti DCH smo primerjali s predlaganimi pravili za nova razreda duktilnosti DC2 in DC3. Potresnoodporno analizo smo izvedli za ravninske modele momentnih okvirov in okvirov z ekscentričnimi povezji z metodo z vodoravnimi silami. Za momente okvire smo izvedli tudi poenostavljeno nelinearno statično analizo. Ugotovili smo, da projektiranje momentnih okvirov po predlogu novega standarda Evrokod 8 dovoljuje nekoliko lažje in vitkejše konstrukcije z manjšimi dimenzijami elementov. Pri tem za dimenzioniranje niso več merodajni vplivi teorije drugega reda, temveč omejitve etažnih pomikov. Nasprotno, upoštevanje pravil predloga novega standarda Evrokod 8 povečuje zahteve nosilnosti in stabilnosti elementov ekscentričnega povezja. Sam postopek projektiranja ekscentričnega povezja se ne razlikuje od obstoječega. Zahteve poostruje povečanje potresnega dela obtežbe potresnega projektnega stanja. Obremenitve elementov ekscentričnih povezij v DC3 in DC2 so bile večje do te mere, da je bilo najbolj smiselno povečati število povezij in ohraniti primerljive dimenzije elementov. The master thesis deals with the changes in the seismic resistance design of structures introduced by the proposal of the new standard Eurocode 8. The novelties were analysed on a practical example of a 5-storey steel building stabilised with moment resisting frames and frames with eccentric bracings. The new definitions of ductility classes, behaviour factors, the interstorey drift sensitivity coefficient and the control of second order effects, the limitations of interstorey drifts in the new limit states and the specific rules for steel buildings were examined. The code requirements from the current Eurocode 8 for ductility class DCH were compared to the proposed rules for the new ductility classes DC2 and DC3. Seismic analysis was performed for planar models of moment resisting frames and frames with eccentric bracings using the lateral force method. A nonlinear static analysis (pushover) for the moment resisting frames was also performed. It was found that the design of moment resisting frames according to the proposal of the new Eurocode 8 allows somewhat lighter and slimmer structures. In this case, the influences of the second order effects are no longer governing, but rather by the limitations of interstorey drifts. On the contrary, following the changes of the new Eurocode 8 means higher resistance and stability requirements for frames with eccentric bracings. Seismic resistance design of frames with eccentric bracings does not differ from current process. The resistance and stability requirements are intensified by the increase of the seismic part of the seismic design state. The internal forces in the frame with eccentric bracings designed for DC2 and DC3 were greater to the point that it was more reasonable to increase the number of eccentric bracings and maintain comparable element dimensions.

Recent years, the demands of building owners have been changed to be able to use the buildings again with small repair cost after an earthquake. The building system with dampers is one structural type which meets these performance requirements. The dampers need good performance and applicability. The RC stud column damper using diagonal de-bonded rebars is one solution. This experimental study shows basic data of the RC stud column damper for design., Article, rights: 社団法人日本建築学会

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.

The structural design of a reinforced concrete building aims at performance based design. With upgrading of required performance, the demand for the building changes to be used with small repair cost even after a severe earthquake. RC members are required to evaluate the damage, and also required good reparability. A beam with de-bonded diagonal reinforcements is very ductile and has good reparability even used as a short beam. To evaluate the load resisting system and the condition of damage level of a member, parametric experimental tests were carried out and a load-carrying model was proposed. After applying this model to the tested results, the design method with less damage was evaluated and investigated by FEM analysis., Article, rights:日本建築学会 rights: 本文データは学協会の許諾に基づきCiNiiから複製したものである relation: isVersionOf: http://ci.nii.ac.jp/naid/110004776296, カテゴリーⅡ

Since the Great Hanshin Earthquake, the demands of people who own buildings have changed: they want to use the buildings again with small repair cost. This requires good reparability of RC members. A beam with diagonal reinforcements is very ductile, however, the diagonal reinforcements yield on the tension side only because concrete struts will work with them on the compression side. When the diagonal reinforcements yield under tension, tension stress is applied to the concrete along the whole length by bond stress. This increases the number of concrete cracks. The results of this experimental investigation demonstrated that debonded diagonal reinforcements are an effective means to reduce damage to short beams and have the same energy dissipation ability as bonded ones., Article, rights:日本建築学会 rights: 本文データは学協会の許諾に基づきCiNiiから複製したものである relation: isVersionOf: http://ci.nii.ac.jp/naid/110004304407, カテゴリーⅠ