1. Potresna analiza in projektiranje izbranih konstrukcijskih elementov armiranobetonske stavbe s povezanimi stenami
- Author
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Veškovo, Andrej and Dolšek, Matjaž
- Subjects
povezane stene ,earthquake-resistant design ,Eurocode standards ,coupled walls ,Evrokod standardi ,seismic analysis ,reinforced concrete ,potresna analiza ,potresnoodporno projektiranje ,armiran beton ,udc:006.76:624.042.7(043.3) - Abstract
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.
- Published
- 2019