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The American ACI 307 design code imposes the use of diagonal rebars at the corners of flue gas inlet regions of reinforced concrete chimneys for mitigating cracks. There is currently no Turkish reinforced concrete design code in effect and the most commonly used chimney construction method is the slip form system. The diagonal rebars impose a difficulty in the construction of the slip form system due to the fact that they cross the line of action of the vertical support elements. In this study, the use of vertical and horizontal corner rebars with similar length and diameter was proposed as an alternative to using diagonal rebars. A detailed finite element model was constructed for a reinforced concrete chimney with a height of 115 m and an opening with a width of 3.7 m and a height of 5.2 m. Nonlinear material models were used for the concrete and rebars. The concrete shell was modeled with hexahedral elements and the rebars were modeled with 2-node bar elements. The design wind loads of the chimney were applied as lateral loads in three different directions. Separate analyses were conducted such that the opening region was located in the tension, compression, and shear zones. The highest tension strains and crack formations were obtained for the case of the opening region in the tension zone. Yield strain limits of the corner rebars were exceeded for the cases of the opening region in the tension and compression zones. The alternative corner reinforcement configuration led to similar results in terms of the opening deformations, crack formations, and corner rebar strains when compared with the original diagonal rebars in all the analyses. It was concluded that the proposed alternative corner rebar configuration can be used in the slip form construction of reinforced concrete chimneys. [ABSTRACT FROM AUTHOR]

The low and mid-rise reinforced concrete buildings are a major part of existing building stock are under serious earthquake hazard. The building stock, where the majority of the population lives, should be evaluated to determine the parameters affecting their earthquake performance. Therefore, inventory study was carried out on approximately 500 residential buildings in Denizli city and around. A total of 144 buildings with 2, 4 and 7 story were modeled considering the inventory study to represent low and medium-rise buildings. Different classes of concrete, reinforcement and regulation cases were reflected in modeling. Also, infill-wall contribution, soft story and heavy overhang irregularities were included in the calculations. Each building was subjected to static pushover analysis and the capacity curves were obtained. The purpose of this study is to examine the changes of the low and mid-rise building periods with the various structural parameters including displacement demands considering the nonlinear behavior. [ABSTRACT FROM AUTHOR]

The goal of this paper is to investigate the non-linear response and to assess the seismic performance of a six story eccentrically braced steel frame (EBF). For this, split-K-braced EBF with high ductility level designed according to the Turkish Earthquake Code-2007 (TEC-07) is analyzed under seven selected earthquake records. The performance of the EBF is assessed considering drift, story and base shear demands, brace and column axial forces and bending moment demands, link beam shear force and rotation demands. Mean values of the demands are used in the performance assessment. The provisions based on capacity design approach specified in TEC-07 for EBFs with high ductility level are discussed by employing the findings. [ABSTRACT FROM AUTHOR]