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V prvem delu diplomske naloge so opisani preizkusi sten JUBHome WALL, ki so bili izvedeni na Zavodu za gradbeništvo Slovenije in Fakulteti za gradbeništvo in geodezijo Univerze v Ljubljani. Trije preizkušanci so bili zasnovani tako, da je v njih prevladovalo upogibno obnašanje, pri desetih pa strižno obnašanje. Osnovni rezultat meritev je odnos med horizontalno silo in zasukom sten. Poškodovanost stene je definirana s štirimi mejnimi stanji: mejno stanje prvih razpok, mejno stanje nosilnosti, mejno stanje blizu porušitve in mejno stanje porušitve. Mejna stanja poškodovanosti so povezana s parametri potresnih zahtev, kot so strižne sile in zasuki sten. V nadaljevanju je opisan postopek določitve faktorja dodatne nosilnosti. Faktor predstavlja razmerje med dejansko nosilnostjo, izmerjeno med preizkusi, in projektno nosilnostjo, ki jo določa standard. Pri stenah s prevladujočim upogibnim obnašanjem smo preko razmerja med najvišjo izmerjeno nosilnostjo in projektno upogibno nosilnostjo določili faktor 1,5. Za stene s prevladujočim strižnim obnašanjem smo glede na razmerje med največjo izmerjeno nosilnostjo in projektno strižno nosilnostjo izbrali faktor 2,0. V zadnjem delu naloge je določen faktor negotovosti pri gradnji, pri čemer smo upoštevali vpliv negotovosti v kvaliteti betonske mešanice in nepravilni vgradnji armature. Faktor je določen na podlagi primerjave nosilnosti sten brez napak in nosilnosti sten z nepopolnostmi za tri razrede kvalitete gradnje, ki so določeni glede na izkušenost izvajalca in kvaliteto nadzora. Ocenili smo, da faktor negotovosti pri gradnji za stene z upogibnim obnašanjem znaša med 1,05 in 1,23. Pri stenah s strižnim obnašanjem je vpliv negotovosti pri gradnji nekoliko večji, saj je najvišja vrednost faktorja nepopolnosti pri gradnji 1,48. The first part of the thesis describes cyclic tests of reinforced concrete walls JUBHome WALL. The tests were performed at the Slovenian National Building and Civil Engineering Institute and at the Faculty of Civil and Geodetic Engineering, University of Ljubljana. Three wall specimens were designed for predominant flexural behaviour, while predominant shear behaviour was anticipated for the other ten specimens. The main results of the tests are presented in terms of hysteretic behaviour of the walls. The damage was characterised by four limit states: the limit state of the first cracks, the limit state of bearing strength, the near collapse limit state and the limit state of collapse, which are related to engineering demand parameters such as shear force and rotation of the wall. The thesis then describes the estimation of the overstrength factor, which is defined as the ratio between the bearing capacity measured in the tests and the design value of bearing capacity. The overstrength factor for walls with flexural and walls with shear behaviour was estimated at 1.5 and 2.0, respectively. In the last part of the thesis, the construction uncertainty factor is determined. It accounts for the potential imperfections in the quality of construction and supervision of construction, which were divided into three quality classes. The construction uncertainty factor of the walls with flexural behaviour was estimated between 1.05 and 1.23. The impact of the quality of construction and supervision is greater for walls with shear behaviour. For the lowest-quality class, the construction uncertainty factor was estimated at 1.48. |
