• ÖZ

Concrete has a significant place in construction structures, is a material that can be easily damaged due to incorrect design, incorrect material selection. Concrete may be damaged by physical and chemical factors. One of these factors is the alkali-silica reaction (ASR). ASTM C1260, is a short-term test method, and ASTM C227, is a longterm test method, are used to measure effect of alkali-silica reaction. In this study, the effect of fly ash additive use with 0, 5, 10, 15, and 20 wt.% replacement of cement was investigated in short- and long-term ASR test methods. For this purpose, while samples prepared for ASTM C1260 were kept in NaOH solution 14-days, samples prepared for ASTM C227 were waited 360-days in normal water solution. As a result; mortar bars with 20% fly ash additive ratio were classified as harmless for ASR in both test methods.

• ÖZ

A previously benchmarked finite element model of a previously tested composite plate shear wall-concrete filled (C-PSW/CF) was used to investigate the influence of three concrete material models on in-plane cyclic inelastic wall response, using LSDyna. The concrete material models considered were the Winfrith, KCC and CSCM, all available in LS-Dyna. Wall moment hysteresis, using the three concrete material models, were obtained and compared. Individual contribution of the steel and concrete to total base moment was investigated for each wall with the three concrete material models. The numerical results obtained using the KCC and CSCM were compared against the benchmarked results obtained using the Winfrith concrete material model. Moment contribution of the steel web and the steel boundary on total base moment of the steel part of the wall and moment contribution of the concrete web and concrete boundary on total base moment of the concrete part of the wall were individually investigated. The wall models with the KCC and CSCM concrete models were observed to cannot capture wall pinching which was captured by the Winfrith concrete model. The wall strength was overpredicted by the CSCM concrete model and predicted reasonably by the KCC concrete model. Average axial stress distribution of the infill concrete was obtained to investigate wall neutral axis and the maximum attained concrete strength using the three concrete models. Concrete axial stress distribution showed some level of confinement for the concrete models considered.

• ÖZ

In developing countries, the need for shelter, working area, shopping and entertainment centers is increasing due to the increasing population effect. In order to meet this need, it is necessary to turn to high-rise buildings. Significant damages have been observed as a result of insufficient horizontal displacement stiffness of high-rise buildings in major earthquakes in previous years. It is known that as the height of the structure increases, the displacement demand of the structure also increases. Since it is accepted that the structure will make inelastic deformation in the design of the structure, these displacements increase to very high levels as the number of stories increases. For this reason, damages can be much higher than expected. In order to limit the level of damage that may occur in high-rise buildings, the horizontal displacement of buildings is limited in many regulations in our age. This limitation is possible by increasing the rigidity of the structures against horizontal displacement. In recent years, the use of shear wall has increased due to the horizontal displacement limitation in the regulations. The use of shear walls in buildings limits the horizontal displacement. However, the choice of where the shear walls will be placed on the plan is very important. Failure to place the shear walls correctly may result in additional loads in the structure. It can also lead to torsional irregularity. In this study, a 10-storey reinforced concrete building model was created. Shear wall at the rate of 1% of the plan area of the building was used in the building. The shear walls are arranged in different geometric shapes and different layouts. The earthquake analysis of 5 different models were performed. Equivalent Earthquake Load, Mode Superposition and Time History Analysis methods were used for earthquake analysis. The results were compared and a proposal was made for the geometry and configuration of the shear wall.

• ÖZ

The behavior of beam-column semi-rigid connection plays an important role in the response of a steel moment resisting, stiffness and rotation capacity framed structure, especially under static loading conditions. In this study, the moment-rotation characteristics of semi-rigid bolted connections using web cleat connections with IPE standard profile is discussed, based on the experimental investigation. The study revealed that the moment resistance of beam-column semi-rigid connection is improved by increasing the height of the beam to the height of web cleat joint (H), and the increasing thickness of web and flange in web cleat joints. The aim was to provide necessary data to improve the Eurocode 3 and efficiently use residue IPE standard profiles, rather than send them back to the consumption cycle. While the resistance moment increased with an increase in H from Hmin to Hmax.

• ÖZ

In order to design a fire-resistant steel structure, the change in the physical and mechanical properties of the steel at high temperatures must be known. As the temperature of steel structural elements increases during fire, their strength decreases considerably. After a certain temperature, these strength drops reach critical levels. Therefore, collapses and various deformations (buckling, arching, etc.) occur. To prevent these collapses during the fire, various fire protection materials must be applied to the structural members such as column and beam. Columns are the most critical structural elements in a steel bearing system. While the possible collapse of the columns may cause the collapse of the whole structure, the beams alone may not cause the collapse of the structure, and the column-beam junctions directly affect the spread of fire. Since there will be many openings and gaps in industrial buildings, the spread and growth of a possible fire becomes very serious. Special fire protection measures are therefore required. In this study, the behavior of a steel industrial structure designed and designed under the influence of Standard Fire (ISO 834) was investigated, the distribution of the temperatures in the structural elements was determined, the required fire protection material was selected, and both protected and unprotected steel temperatures were determined. This design against fire is designed to provide fire resistance for 1 hour (60 min) for this structure. During this period, the type and optimum thickness of the protection material to be applied before reaching the critical temperature values for which the strength of the steel material would lose and would be damaged and compared with the temperatures that would occur in the structural elements without applying fire protection. According to the findings of the study, it was concluded that 25 mm drywall box protection material should be applied on the inner columns and 20 mm on the edge columns and 15 mm on the corner columns. In addition to this, it was concluded that spray beams (intumescent coating) of different thicknesses between 15-20 mm were applied to the beams depending on the location and the load to be affected and the type of joint. After these applied passive fire protection materials, the temperatures obtained in the structural elements reached to 500-550 as a result of 1- hour fire design. These temperatures are acceptable temperature values given the strength drop in critical temperature ranges for steel under the 1-hour fire condition.