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The use of reinforced concrete shear walls is inevitable in earthquake-resistant building design. For this reason, it is important to understand the effect of shear walls used in buildings designed in earthquake zones on structural behaviour. In addition, it is necessary to reveal the behaviours for linear and non-linear calculation methods in buildings with shear walls. In this article, 12 building models were created in 4 different floor plans with 6, 9 and 12 storeys, having frame structural systems with shear walls, respectively, to represent low, medium and high-rise buildings. Linear and nonlinear (pushover and non-linear time history (NTH)) analyses of the created building models were carried out with the Sta4- Cad program and their linear and nonlinear behaviours were compared. The results obtained from linear structural analyses reveal that if shear walls are placed on the outermost axes, they will become more unfavourable as the building height increases. The results obtained from pushover and NTH analyses show that if the placement of the shear walls approaches the centre, the damage level in the beams increases as the building height increases, in contrast with the damage level in the vertical structural elements decreases. In addition, while the effect of beam damage is greater in the pushover analysis at performance levels, it is seen that the damage effect on vertical structural elements is greater in the NTH analysis. [ABSTRACT FROM AUTHOR]

Agricultural production has both increased and become more efficient with the development of technology. However, greenhouse gases such as CO2 released into the air during production cause climate change. This situation also affects agricultural productivity. Therefore, the main objective of this paper is the examine the interaction between agricultural sector activity and CO2 emissions in Türkiye in a non-linear framework. For this purpose, the Maki cointegration test and the Single Fourier frequency Toda & Yamamoto causality test were used to investigate the interplay between agricultural value added and CO2 using time series data covering the period from 1968 to 2018. In addition to the empirical analysis developed in the paper, our study adds to the literature by studying the relationship between CO2 and energy consumption in the agricultural sector, as opposed to studies that use aggregate CO2 emissions as an indicator of climate change. In addition, the short- and long-run interactions between CO2 and agricultural productivity were investigated by estimating two separate equations where agricultural productivity and CO2 emissions are used as dependent variables. The Maki cointegration test cointegration test shows the existence of a long-run relationship between agricultural value added and CO2 emissions under structural breaks. The detected significant breaks are associated with significant events affecting the Türkiye economy. For instance, when agricultural value added is the dependent variable, the break dates of 1971 and 1974 coincide with the oil crisis, while the breaking dates of 2002 and 2008 coincide with Türkiye's 2001 financial crisis and the 2008 global financial crisis. Similarly, the break dates of 1973 and 1977 obtained in the CO2 equation are associated with the 1970s' global oil crisis. Long-run parameter estimates derived from FMOLS and CCR estimators indicated that CO2 emissions have a long-run, positive and significant impact on agricultural productivity. In addition, the long-run results support the existence of a positive and significant impact of agricultural productivity on environmental degradation. The gradual shift causality test also supports the presence of one-way causality, running from agriculture output to CO2. [ABSTRACT FROM AUTHOR]

This paper investigates the effect of fiber on the behavior of punching shear slabs; a finite element modeling approach is used to simulate the case study. The proportion mix of hybrid fiber-reinforced concrete, which contains 0.2 percent macro synthetic fibers and 0.68, 0.8, and 0.96 percent steel fibers, compressive strengths of 50 MPa, different longitudinal reinforcement used, and slab thicknesses of 150, 200, and 250 mm are all joined and investigated in this study. The ATENA software is used to perform nonlinear finite element analysis. The slab results validation was done similarly to previous experimental work, and the acquired results indicated a significant agreement. Thirty-six two-way specimen slabs with dimensions of 1900 × 1900mm were modeled in this investigation. All four sides of the slabs are supported. The results showed that the slabs' ultimate shear capacity increases with increasing the hybrid steel fiber. Nevertheless, the ultimate capacity of the slabs has decreased due to an increase in the reinforcement ratio and slab thickness. [ABSTRACT FROM AUTHOR]

In this study, non-linear analysis is considered under the Evaluation and Design Based on Strain (ŞGDT) criteria specified in the regulation, of a high reinforced concrete structure with a height of 72 m according to the Turkish Building Earthquake Code (TBDY) 2018 under the Earthquake Design Class 1 (DTS) category. Considering the performance and structural behavior of different flooring types, comparisons were made. Within the same vertical support system, 4 different models, commonly used in reinforced concrete structures, consisting of conventional slab system, ribbed hardy slab system, flat slab system and non-modeled floor conventional slab system were considered. The same strength properties are included in the material selection of the concrete and reinforcement used for each building system. Inelastic strains obtained from the analyses were compared with each other and performance levels were determined according to different flooring types. As a result, in non-linear behavior analysis, it has been observed that modeling of slabs can change the element damage levels and building behavior, contributing to the horizontal in-plane rigidity of the building systems and causing more strain on the vertical elements. [ABSTRACT FROM AUTHOR]

In masonry structures, determination of a structural behavior and load-bearing capacity becomes quite complicated when irregular wall bond patterns and the damages developing in load-bearing elements are considered, as well as the unclear in the material parameters. In these cases, preferring simplified approaches in a numerical analysis allows to obtain solution practically. In this study, in-plane damage developments and load-bearing capacities of masonry structure were tried to be determined using a numerical analysis model consisting of truss elements. In this method, which was proposed as an innovative approach in terms of use in masonry structures, frame elements that only load-bearing in the direction of the longitudinal axis were used. Thus, in the structure, it was aimed to obtain the maximum load-bearing capacity and damages that may occur, under external loads with the nonlinear analyzes performed by the equivalent calculation model. In the study based on masonry structures discussed in the literature previously, the advantages and disadvantages of the method were evaluated comparatively. Although the ductility response of a real structure couldn't be fully represented, it was observed that the maximum load-bearing capacity and damage formation zones could be determined with acceptable accuracy. Consequently, the equivalent truss model approach, which is proposed as an alternative to the commonly preferred detailed modeling procedures, is promising. [ABSTRACT FROM AUTHOR]

In this paper, a shear deformable force-based frame finite element with semi-rigid connections is derived for nonlinear analysis of steel structures. Distributed plasticity approach is defined along element length and section depth, and linear or non-linear semi-rigid connection behavior can be specified anywhere along elements without the necessity to define additional nodes and to increase the degrees of freedom of the structural system. To perform vibration analyses with similar accuracy, force-based consistent mass matrix is used considering semi-rigidity in connections and an appropriate shear correction coefficient for I-sections. The element formulation is presented in 2 dimensions to simplify the formulation, and numerical validation and comparison studies are carried out on complex and irregular structures in 2-D and 3-D. In models with semi-rigid connections, the effect of nonlinear behavior on the structural system has been studied in both beam-column and column-bases. In the presented examples, it was possible to push structures higher than the existing displacements, and it was revealed that the nonlinear behavior in the column-base connections could create much more critical results for the structural systems with P-Delta effects. In addition, high-level accuracy results were obtained when performing vibration analyses with the application of force-based consistent mass matrix. [ABSTRACT FROM AUTHOR]

In this study, a graphical interface has been developed to the BESAM program which written in fortran code prepared within the scope of TUBITAK 111M119 project in order to overcome the difficulties in the nonlinear behaviour model. The lack of a graphical interface for engineers forces users to create cross-section models in text files in certain formats, which is a challenging and time-consuming process. A pre-process helps to create appropriate structural models, to enter and control data, to select appropriate analysis parameters, and to determine appropriate loads. In addition, the graphical capabilities allow the user to view sections, make various visual adjustments, and graph the results of the analysis. Thanks to the software developed, the behaviour of reinforced concrete structural members can be computed practically according to the determined deformation criteria. This information can be gathered in a file and easily transferred to commonly used analysis programs using data transfer features. The software can graphically show the moment-curvature relationships for reinforced concrete sections. [ABSTRACT FROM AUTHOR]

Silos are slender structures with thin sections that can react differently according to the fullness ratios against any impact that may come from inside or outside. Silo structures can be manufactured in a variety of materials and sizes for different storage needs. In large diameter silos, most of the weight of the structure is the stored material. The load carrying system stands out with its dimensions rather than its weight. Considering the dimensional parameters of large diameter silos, external factors, such as wind affects the structure highly. On the other hand, the type and characteristics of the stored material changes the internal loading conditions drastically. One of the main problems of these situations is the sloshing, which is a dynamic load that can occur in fluid storage. In this paper, cylindrical steel liquid storage silos are discussed. Twelve numerical models with different plate combinations created for three different diameter sizes are created with the consideration of same amount of stored liquid and silo height for all models. Created models are analyzed under dynamic and static loads. The results of the analysis are examined comparatively, and the variation of plate efficiency between combinations and diameter differences are interpreted. From the analysis results, it has been determined that the effectiveness of the stiffening plates is in dimensional relation with the silo diameter. In conclusion, it is suggested that altering the plate dimensions (size and thickness) along with the silo diameter will contribute to the rigidity of the structure. [ABSTRACT FROM AUTHOR]

In order to protected against destructive effects of earthquakes, the rules that have developed for earthquake resistant design of buildings have been transformed into performance-based design conditions that demands special requirements for different type of structures. Steel structures should be reinforced with brace members and joint details should provide suitable ductility conditions in order to safely carry the horizontal forces that occurs due to earthquake effect. The gusset plates that provide the connection of brace members to structural elements are expected to affect the earthquake behavior of braced steel structures. This study conducted analytically to investigate the earthquake behavior of braced steel frames with different gusset plate designs. Seven real earthquake records were selected and scaled for the purpose of satisfying analysis criterions to perform nonlinear time history analyzes. In addition, the five storey braced steel frames that designed in accordance with the current codes and standarts were examined. The structures that designed with the gusset plates, which have different thicknesses, were modeled via OpenSees software and the effect of gusset plate thickness on the structural responses was evaluated. [ABSTRACT FROM AUTHOR]

This study investigates the effect of the depth of the slot on the behavior of double-slotted RC beam (DSB) systems under monotonic loading by utilizing finite element analysis. Firstly, 3D nonlinear finite element analyses of three experimentally tested specimens in literature were performed in order to examine the ability of the numerical model to predict the experimental behaviour. In the second part of the research, this verified numerical model was used to investigate the effect of the depth of the slot on the beam behavior by changing the slot depth. The slot depth / beam height ratio was assumed to be 0.125, 0.150, 0.200, 0.300 and 0.400 in the parametric study. None of the geometrical properties and reinforcement details were modified in these analyses as the control variable was the depth of the slot. During analyses, the vertical load effect on the column and the monotonic displacement at the end of the cantilever beam were taken into account. In addition, nonlinear material properties of concrete as well as reinforcing steel were considered. The performance of models were classified by comparing the load, displacement and rotation capacities of DSB systems. As a result, it was observed that the slot depth / beam height ratio of 0,300 performed better for each plastic hinge location. [ABSTRACT FROM AUTHOR]

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]

In Turkey, majority of the living areas is located on earthquake zones. However, uncontrolled growth of population and urbanization have been occurred as a result of the immigration associated with industrialization. The rapid and uncontrolled growth has caused unplanned and insecure constructions in our cities. The urban renewal process for eliminating the situation and creating safe and planned cities associated with social reinforcement areas has lead to many problems. The most important one of these problems is the demolishment works which do not fit in scientific and art regulation rules. In this project, the structural damages on a building which is located next to the demolishment area and their influences on the building performance under earthquake have been studied and the structural analysis via the process of model samples showed that the whole system must be strengthened rather than the bearing members in a defined area. [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 aim of this study is to assess the efficiency of changing thickness of end plate and reinforcing panel zone in bolted end plate column-beam connections that are performed by finite element analyses under monotonic loading. In the first phase of the study, finite element analyses of two bolted end plate connections which were taken from literature were performed and the experimental results from the literature and the numerical results of the present study were compared. In the second phase, effects of increasing the end plate thickness and the effects of reinforcing panel zone of connections, taken from the literature, were investigated. To reinforce the panel zone, diagonal braces or column web doubler plates were used. Pretensioned bolts were used in connections and monotonic displacement loading are applied to end of cantilever beam. Material and geometry nonlinearities were considered in the analyses. The linear or nonlinear contacts between connection parts such as column, beam, bolt and plate were considered. Connections were evaluated in terms of loading capacity, moment - rotation curve, plastic strain distributions of panel zone and bolt tension forces. The results reveal that reinforcing panel zone causes the plastic strains of column panel zone to decrease but resulting in earlier buckling of beam flange and beam web and reductions in the rotational capacity of the connection. [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]

Chemical anchors are widely used to ensure transfer of the loads between the structural elements which are constructed at different times. A significant part of these anchors are exposed to shear loads. Therefore, investigation of the anchor behavior under shear loads is important. In this study, nonlinear modelling is verified for determining shear behavior of anchors ensuring load transfer between the structural elements constructed different times by using ANSYS Software that is widely used in different engineering disciplines. The effect of the changes in parameters used as input to the results is investigated. As a result, it is discussed that, small changes in input parameters on the same model can expose very different results. [ABSTRACT FROM AUTHOR]

In this study, yield criteria proposed to model plastic behavior of concrete are presented. The well-known criteria, Drucker-Prager, von Mises and Mohr Coulomb used to determine stress state of concrete, that is elastic or plastic, are included in most of all packet programs which are used in the analysis of reinforced concrete structures. In addition, there are some criteria proposed for concrete such as Bresler-Pister, Hsieh-Ting-Chen and Ottosen. In this study, yield surface of these yield criteria are demonstrated in deviator stress surface and related equations are presented. Also, in order to model nonlinear analysis of reinforced concrete structures, a program is coded in MATLAB and a reinforced concrete beam is analyzed as a plane stress problem using this program. The results obtained in this study are compared with the experimental and analytical results taken from the literature. These results show that the developed program can be effectively used in nonlinear analysis of reinforced concrete beams. [ABSTRACT FROM AUTHOR]

Two alternative methods exists for the nonlinear analysis of reinforced concrete members that are widely used in today's construction industry, namely, having a laboratory testing of sample members and analysis by developing computer simulation models. Laboratory testing is limited, often costly, and took long times considering the member sizes, support conditions, loading etc. This study aims to compare the actual laboratory test results of simply supported beams having rectangular cross-section subjected to monotonic loading with the results of the nonlinear finite element model developed for ANSYS structural analysis software. Thus, a computer model that can best represent the actual behavior tried to be achieved. [ABSTRACT FROM AUTHOR]