A comparative study on the seismic provisions of different codes for RC buildings

Huseyin Bilgin,Marijana Hadzima-Nyarko,Ercan Işık,Hayri Baytan Ozmen,Ehsan Harirchian 국제구조공학회 2022 Structural Engineering and Mechanics, An Int'l Jou Vol.83 No.2

Significant structural damages due to earthquakes reveal the importance of seismic design provisions. This paper presents a comparison between the seismic design provisions of Albania, Croatia, Iran, and Turkey for the design of mid-rise reinforced-concrete (RC) frames. Information on the historical development of the considered provisions are given. The code provisions are compared, illustrating the main differences in the minimum requirements for column and beam detailing and analysis for mid-rise RC frames. 4-story, 5-story, and 6-story buildings are designed according to each design code, and their performance is evaluated comparatively by using a displacement-based adaptive pushover procedure and eigenvalue analysis. It is observed that recent Turkish code has the highest and Albanian code has the lowest level of requirements in terms of member size and reinforcement detailing. The considered models indicate 15%, 20% and 50%, lower period values than the Croatia, Iran and Albania buildings, respectively. Additionally, building models per Croatia, Iran and Albania codes have 30%, 35% and 65% less base shear capacity when compared to Turkish building codes. Building models per Croatia and Iran codes indicate similar properties both in terms of strength and stiffness.

Seismic performance of existing low-rise URM buildings considering the addition of new stories

Neritan Shkodrani,Huseyin Bilgin 국제구조공학회 2021 Structural Engineering and Mechanics, An Int'l Jou Vol.79 No.6

In low-rise unreinforced masonry (URM) buildings, structural design is generally performed considering the load effects induced by seismic forces as well as the vertical loads. However, there might be cases where the additional or unforeseen loads may be encountered during the lifespan of these buildings. The loads that are induced from the addition of a new storey during the service life is a good example for these additional loads. Since the reconstruction licenses and building height limits specified by the local authorities may vary in life cycle of the structures, it is important to decide the addition of a storey to an existing building considering the structural safety concerns. In this study, an existing low-rise URM building is modelled with added stories (subsequently planned after its construction), and numerical analyses are carried out considering the extra loads of this additional stories. The aim of this study is to assess the earthquake performance of the structures considering this unforeseen situation which was not considered in the original structural design. The suitability of the initial structural design project to the existing building was examined by the site investigations. The results of the analytical analysis were compared with the seismic code requirements, and the seismic performance level of the building is estimated. The study is intended to be useful in determining the path to be followed for the determination of the seismic capacity if existing buildings are exposed to such additional loads. The findings of this study could be used to design local and global retrofitting works. Especially, for the typologies underwent such interventions, solutions that reduce earthquake demands by providing high lateral strength and rigidity could be considered. It is believed that the outcomes obtained with respect to the evaluation of this case study could be generalized to a wide variety of such template buildings and extrapolated for a wide masonry building type.

Seismic performance evaluation of school buildings in Turkey

Inel, Mehmet,Ozmen, Hayri Baytan,Bilgin, Huseyin Techno-Press 2008 Structural Engineering and Mechanics, An Int'l Jou Vol.30 No.5

This study evaluates seismic performance of the school buildings with the selected template designs in Turkey considering nonlinear behavior of reinforced concrete components. Six school buildings with template designs were selected to represent major percentage of school buildings in medium-size cities located in high seismic region of Turkey. Selection of template designed buildings and material properties were based on field investigation on government owned school buildings in several cities in western part of Turkey. Capacity curves of investigated buildings were determined by pushover analyses conducted in two principal directions. The inelastic dynamic characteristics were represented by equivalent single-degree-of-freedom (SDOF) systems and their seismic displacement demands were calculated under selected ground motions. Seismic performance evaluation was carried out in accordance with recently published Turkish Earthquake Code that has similarities with FEMA-356 guidelines. Reasons of building damages in past earthquakes are examined using the results of performance assessment of investigated buildings. The effects of material quality on seismic performance of school buildings were investigated. The detailed examination of capacity curves and performance evaluation identified deficiencies and possible solutions for template designs.

Seismic performance evaluation of school buildings in Turkey

Mehmet Inel,Hayri Baytan Ozmen,Huseyin Bilgin 국제구조공학회 2008 Structural Engineering and Mechanics, An Int'l Jou Vol.30 No.5

This study evaluates seismic performance of the school buildings with the selected template designs in Turkey considering nonlinear behavior of reinforced concrete components. Six school buildings with template designs were selected to represent major percentage of school buildings in medium-size cities located in high seismic region of Turkey. Selection of template designed buildings and material properties were based on field investigation on government owned school buildings in several cities in western part of Turkey. Capacity curves of investigated buildings were determined by pushover analyses conducted in two principal directions. The inelastic dynamic characteristics were represented by equivalent single-degree-offreedom (SDOF) systems and their seismic displacement demands were calculated under selected ground motions. Seismic performance evaluation was carried out in accordance with recently published Turkish Earthquake Code that has similarities with FEMA-356 guidelines. Reasons of building damages in past earthquakes are examined using the results of performance assessment of investigated buildings. The effects of material quality on seismic performance of school buildings were investigated. The detailed examination of capacity curves and performance evaluation identified deficiencies and possible solutions for template designs.

Examination of protective and therapeutic effects of ruscogenin on cerulein-induced experimental acute pancreatitis in rats

Gulcin Ercan,Rumeysa İlbar Tartar,Ali Solmaz,Osman Bilgin Gulcicek,Onur Olgac Karagulle,Serhat Meric,Huseyin Cayoren,Ramazan Kusaslan,Ahu Kemik,Damla Gokceoglu Kayali,Sule Cetinel,Atilla Celik 대한외과학회 2019 Annals of Surgical Treatment and Research(ASRT) Vol.97 No.6

Purpose: To determine the potential protective and therapeutic effects and action mechanism of ruscogenin on ceruleininduced acute pancreatitis (AP) model in rats. Methods: Overall, 32 rats were attenuated to the sham (2-mL/kg/day isotonic solution for 4 weeks), control (20-μg/kg cerulein-induced AP for 12 hours), prophylaxis groups (cerulein-induced AP following 3-mL/kg/day ruscogenin for 4 weeks) and treatment (3-mL/kg/day ruscogenin following cerulein-induced AP for 12 hours). Blood samples were collected for biochemical analysis of nitric oxide synthase 1 (NOS1/neuronal NOS), malondialdehyde (MDA) and intercellular adhesion molecule 1 (ICAM-1). After sacrification, pancreas tissues were collected and prepared for light microscopic (hematoxylin and eosin), immunohistochemical (nuclear factor kappa B) and biochemical analysis (tumor necrosis factor-alpha [TNF-α], interleukin-6 and 1β [IL-6 and IL-1β], CRP, high-sensitivity CRP [hs-CRP] amylase, lipase, and ICAM-1). Ultrastructural analysis was performed by transmission electron microscopy. Results: The protective and therapeutic actions of ruscogenin were accomplished by improvements in histopathology, by decreasing blood cytokine levels of CRP, hs-CRP levels, TNF-α, IL-6, IL-1β, ICAM-1, by reducing the pancreatic enzymes amylase and lipase in blood, and by suppressing the expression of nuclear factor kappa B, ICAM-1, and NOS-1, but not MDA in pancreatic tissues. Ruscogenin also improved cerulein-induced ultrastructural degenerations in endocrine and exocrine cells, especially in treatment group. Conclusion: The present findings have demonstrated the beneficial protective and therapeutical effects of ruscogenin, nominating it as a highly promising supplementary agent to be considered in the treatment of AP, and even as a protective agent against the damages induced by disease