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Understanding the behavior of structures during earthquakes is crucial for ensuring safety. Despite their significant impact on buildings, infill walls are often overlooked in seismic assessments, contributing to the complexity of a structure. Because of their intricate nature and modeling difficulties, infill walls are frequently excluded from seismic models. However, given the prevalence of reinforced concrete buildings with various infill wall materials in earthquake-prone areas, it is essential to incorporate infill walls for a more realistic evaluation of seismic behavior. This study scrutinizes a building that sustained damage in the Izmir earthquake in Turkey. The building was represented in four distinct models using the SAP2000 V24 finite element program: without infill walls, with porotherm clay blocks, burnt clay brick, and autoclaved aerated concrete blocks. Real parameters of the building were utilized in the modeling process. Upon comparing the results of the time history analysis, it was observed that the presence of infill walls had a positive impact on various building properties, including period, ground floor shear force, column bearing capacity, and inter-story drift ratio. Additionally, infill walls increased base shear forces on the ground floors and the overall base shear force. Notably, similar outcomes were obtained with porotherm clay blocks and burnt clay brick as infill wall types, while autoclaved aerated concrete blocks exhibited lower stiffness than other infill wall models. [ABSTRACT FROM AUTHOR]

Copyright of Omer Halisdemir Universitesi Iktisadi ve Idari Bilimler Fakültesi Dergisi is the property of Omer Halisdemir University, Faculty of Economics & Admistrative Sciene and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Historical masonry structures, which constitute an important part of the historical heritage, exhibit brittle behavior under tensile stresses due to earthquakes or soil movements/settlements. Therefore, they are sensitive to deformation. The soil–structure interaction problems play an important role in the damage to historical masonry structures. Different settlements, slips, and deformations in foundations causes damage to, and/or partial collapse the load-bearing walls. This study provides a numerical simulation of a historic masonry building on the north coast of Turkey, dating from 19th century, which suffered severe damage due to soil settlement by excavation activity near the building. FE models of the building with and without the soil–structure system were created to identify the damage to the building following soil settlement. The height of the soil domain (bounded as a fixed boundary condition) was accepted in the range of 1.5 m to 15 m. The damage propagation between the numerically obtained damage and the existing damage to the building was detailed and compared. In terms of displacement, the maximum vertical and horizontal displacement values reflecting the existing damage to the building were determined as 22 mm and 85 mm, respectively. The soil depth of 6 m was also considered acceptable for deciding the soil–structure interaction. For this, the sum of the rigid basement and the soil depth can be selected to be equal to the total height of the building participating in free vibration. It was concluded that the numerical procedure employed provided an effective representation of existing damage to a building due to soil settlement. Moreover, the procedure described can be adopted for possible collapse simulation. [ABSTRACT FROM AUTHOR]

Using a non-linear autoregressive distributed lag time-series analysis, this paper investigates the causal relationship between climate change, the tourism sector, and energy consumption in Turkey. The trade-off between a country's economic growth and the environmental degradation caused by tourism and the energy sector is critical in terms of scientifically addressing the issue and developing economic policies. As a result, climate change is used as the dependent variable and is represented by precipitation and temperature separately; the independent variables are tourist arrivals, energy consumption, and economic growth. Data is gathered by various institutions from 1995 to 2020. According to the test results, while positive and negative shocks contribute to the decrease in precipitation and temperature in renewable energy consumption (REC) in the long-run, they affect the increase in precipitation and temperature in non-renewable energy consumption (NREC). In the long-run relationship between tourism and temperature, a decrease in the number of tourist arrivals causes a decrease in temperature and precipitation. The findings reveal that a decrease in the number of tourist arrivals and an increase in REC may aid in decreasing temperature, while the increase in NREC may cause an increase in temperature. Through a case study of Turkey, decision-makers should consider these scientific findings that are in the frame of non-linear analysis as possible scenarios for mitigating climate change and fostering sustainable economic growth with efficient tourism policies for the world. [ABSTRACT FROM AUTHOR]

In this study, the cracking and maximum torsional moment values of reinforced concrete walls obtained from the experiments were compared with those obtained from finite element analyses and various standards. Reinforced concrete walls were designed according to the Turkey Building Earthquake Code 2018 (TBEC 2018) and the Turkish Standard 500 (TS500 2000). The purpose of this study is to compare the cracking and maximum torsional moments of reinforced concrete walls obtained using different methods. Data from the reinforced concrete wall tests were used for comparison. After the experimental tests, the ANSYS finite element program was used to perform numerical analyses. Finally, TS500 2000, ACI 318–14, and Eurocode 2 were used to obtain the theoretical values of the cracking and maximum torsional moment. All the data obtained from the three methods were compared and evaluated using tables and graphics. When the results are compared considering the length/width ratios (aspect ratios) of the walls, the calculation results show that the larger cross-section reinforced concrete walls have higher cracking and maximum torsional moments. It was determined that there was a 50% increase in the average cracking torsional moment with an increase in the aspect ratio from 5 to 7. This increase was calculated as 33% at the maximum torsional moment. When the results are compared according to different methods, it was observed that the cracking torsional moment values obtained from ANSYS analyses were similar to those obtained from the standards. The experimental cracking torsional moments were higher than those obtained using the other two methods. The maximum torsional moments obtained from the three methods were similar. The analysis results show that the standard-based calculations offer more conservative results. [ABSTRACT FROM AUTHOR]

This study describes the seismic assessment of the Archangeloi (Başmelekler) Church in Kumyaka (Sige), Türkiye. The Archangeloi Church is an important religious monument that has survived to the present day from the eighth century. Through field surveys, the structural system, damages and masonry texture were determined. Pushover analysis was performed with OpenSees software, which has an advanced nonlinear analysis capability. The Damage TC3D material damage model with advanced features was used, allowing a more stable and effective application of mixed implicit–explicit analyses. Displacement-based pushover analyses were performed with different control points, and the damage patterns, ultimate strength and strength reductions were obtained effectively. The pushover analysis reflected the structure's expected behavior, especially its post-ultimate strength and failure patterns, owing to the material damage model's advanced mixed implicit–explicit capacity. Kinematic analyses were performed to determine the overturning mechanisms. Due to the analysis assumptions and pre-assigned failure mechanisms, lower failure multipliers were obtained with the kinematic analysis than with the pushover analysis. Under seismic loading, the structure did not satisfy the required performance targets. Extensive damage occurred throughout the structure, even at the lowest performance levels. The selected modeling/analysis method and material damage model to determine this church's structural performance reflect the expected structural behavior. [ABSTRACT FROM AUTHOR]

Seismic structural assessment of masonry arch bridges is essential due to their cultural, economic and strategic importance and vulnerability. A realistic and rigorous structural assessment is necessary in order to protect the bridges and use resources carefully. At this time, there are no standardised or widely accepted assessment procedures, and the performance criteria for masonry arch bridges are not available. This study presents an overarching reliability-based seismic assessment methodology based on analytical modelling, laboratory testing and probabilistic assessment. It investigates the performance criteria concept and proposes performance limit states. The methodology is applied to a historical masonry arch bridge in Turkey. To consider rigorously the uncertainties in material properties and seismic input, probabilistic nonlinear analyses are conducted using a detailed 3D finite element model. The results are combined with the proposed limit state definitions to generate the capacity and demand distributions. Both distributions are used in Monte Carlo simulation and First-Order Reliability Method (FORM) to estimate the probability of exceedance and reliability indexes for each limit state. The proposed probabilistic assessment methodology will be a useful approach to obtaining more reliable information about masonry arch bridges' expected seismic performance and for better-informed decision-making, especially when designing intervention actions and post-earthquake scenarios. [ABSTRACT FROM AUTHOR]

The income inequality-economy link has been argued by researchers a long time. But the impact of income inequality on environmental pollution is a new investigation topic for developing countries. Turkey is well known as an emerging economy which has a high level of income inequality and CO2 emissions. Therefore, this paper concentrates on the income inequality-CO2 emissions link in Turkish economy by applying a nonlinear analysis. This paper integrates economic growth and financial development to the CO2 emissions specification over the period of 1987–2019. We employ the nonlinear autoregressive distributed lag approach to explore the long-run nonlinear linkages between the series. Our findings reveal an asymmetric cointegration among variables. Positive and negative income inequality shocks positively affect CO2 emissions implying that positive and negative shocks of income inequality enhance CO2 emissions in the long run. Negative economic growth shocks decrease CO2 emissions, while positive shocks to financial development increase CO2 emissions in the long run. We provide important policy suggestions that might be useful to the policymakers to decrease CO2 emissions in Turkey. [ABSTRACT FROM AUTHOR]

This article presents a nonlinear analysis in Turkey on the effect of an environmental tax (ET) on the ecological footprint (EFP) and carbon dioxide (CO2) emissions. In the literature, most of the studies examining the effects of environmental taxes (ETs) on environmental degradation (ED) have used linear methods. The number of studies examining this relationship with nonlinear methods is few. However, there is no study examining the long-run effects of ETs on the EFP, which is one of the most important indicators of ED, using nonlinear analysis. This study contributes to the literature by investigating the long-run effects of ETs on EFP and CO2 emissions in Turkey by nonlinear analysis. Therefore, the model consisting of annual data for the period 1994–2019 was estimated by Dufrénot et al. (2006) nonlinear cointegration test. According to the estimation results obtained, ETs do not have any long-run effects on EFP and CO2 emissions. Accordingly, it can be concluded that ETs in Turkey do not affect preventing ED. [ABSTRACT FROM AUTHOR]

We aim at examining the asymmetric relationship between foreign direct investment (FDI) and economic growth by adding renewable and non-renewable energy consumption, labor, and capital for Turkey in 1987-2015 period. For this purpose, non-linear ARDL test is employed for the first time to analyze the link amongst the variables in the context of Turkey. Our results confirm that all variables included into model have positive effects on economic growth. For example, while 1 % increase of positive shock in FDI increases economic growth by 0.053 %, 1 % increase in negative shock decreases economic growth around 0.057 % in Turkey in the long-run. Furthermore, since non-renewable energy contributes to economic growth nearly two times higher than renewable energy, Turkish economy is dependent on imported fossil fuels rather than renewable energy sources. Our study highlights the importance of energy efficiency and productivity issues in Turkey. Policy implications of obtained results are presented at the end of the study. [ABSTRACT FROM AUTHOR]

Seismic performance of existing liquid pentane storage tanks located in a tank farm in Turkey Kocaeli region, which is a high seismic region, is studied. The tanks are free-to-slide on their existing reinforced concrete foundation. The tanks seismic performance is evaluated based on the 2018-Turkish Building Seismic Code and API 650 provisions using three-dimensional (3D) finite element methods with nonlinear time-history analysis. The developed FE model for seismic performance assessment of the existing tanks includes tank-foundation dynamic interaction, tank supports uplifting, and sliding over the foundation. The study revealed poor and inadequate seismic performance for the existing tanks due to lack of tank foundation-anchorage. A practical seismic retrofit strategy is developed to anchor the tanks to the existing reinforced concrete foundation. Prefabricated and field-welding free steel split sleeves are developed for the tank anchorage. The retrofitted tank seismic performance is evaluated to verify the proposed retrofit strategy and its effects on tank seismic behavior. The base shear and uplift reactions for the retrofitted tank are monitored for the anchorage design. Tank top drift, which is an important seismic performance parameter for tank piping, and tank steel material yielding are also checked to verify adequacy of the proposed retrofit strategy. [ABSTRACT FROM AUTHOR]

The response spectra of multidimensional analyses are compared with one-dimensional (1D) local models to couple the irregular soil stratification effect at a site. In recent studies, the surface motion 2D/1D or 3D/1D spectra ratios are defined as the spectral aggravation factors for each region of a site. Particularly in alluvial basins, where the soil media is typically formed by fault ruptures or topographic depressions filled with sediments, the inclination of the rock outcrop at the edge of the basin has a considerable effect on the site response, and such an effect has not yet been taken into consideration in recent seismic building codes and general engineering applications. In this study, the natural alluvial basin near the North Anatolian Fault in Gemlik, Marmara region, Turkey, was investigated by 40 seismic site tests and 4 validation borings. The 2D and 1D nonlinear response history analyses in the north–south and east–west directions in the Gemlik basin were performed by numerical models on a finite difference scheme considering nonlinear elastoplastic material behaviors and geometric discontinuities. Twenty-two strong ground motions recorded at the rock site were excited vertically as SH waves. The numerical results showed that narrow basin effects were derived not only by reflection, refraction, and shifting behavior but also by the focusing and superposition of the seismic waves propagating from opposite basin edges. As a result, the site-specific spectral aggravation factors SAF2D/1D defined by the ratio between the 2D and 1D acceleration response spectra for each period and any location on the site were proposed for the Gemlik basin. The variations in the aggravation factors were observed as values increasing to 1.2–2.2 near the edge and at the basin center. [ABSTRACT FROM AUTHOR]

Copyright of Istanbul Commerce University Journal of Social Sciences / İstanbul Ticaret Üniversitesi Sosyal Bilimler Dergisi is the property of Istanbul Commerce University Journal of Social Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Reconnaissance studies performed after destructive earthquakes have shown that seismic performance of existing buildings, especially constructed on weak soils, is significantly low. This situation implies the negative effects of soil-structure interaction on the seismic performance of buildings. In order to investigate these effects, 40 existing buildings from Turkey were selected and nonlinear models were constructed by considering fixed-base and stiff, moderate and soft soil conditions. Buildings designed before and after Turkish Earthquake code of 1998 were grouped as old and new buildings, respectively. Different soil conditions classified according to shear wave velocities were reflected by using substructure method. Inelastic deformation demands were obtained by using nonlinear time history analysis and 20 real acceleration records selected from major earthquakes were used. The results have shown that soil-structure interaction, especially in soft soil cases, significantly affects the seismic response of old buildings. The most significant increase in drift demands occurred in first stories and the results corresponding to fixed-base, stiff and moderate cases are closer to each other with respect to soft soil cases. Distribution of results has indicated that effect of soil-structure interaction on the seismic performance of new buildings is limited with respect to old buildings. [ABSTRACT FROM AUTHOR]

In this paper, we assess the asymmetric effects of exchange rate changes on the trade balance of 57 industries that trade between Turkey and EU. Since the analysis introduces nonlinear adjustment of the exchange rate, we find results that are different than previous research. More precisely, we find short-run asymmetry effects in all industries, short run adjustment asymmetry in 24 industries, short-run impact asymmetry in 17 industries, and long-run asymmetry effects in 23 industries. Small and large industries seem to be subject to the same asymmetry effects. [ABSTRACT FROM AUTHOR]

The Western Anatolia Region of Turkey is an important region of high seismic activity. The active dynamics of the region are shaped by a compression and expansion mechanism. This active mechanism is still ongoing and causes strong seismic activity in the region. The Frontinus Gate is a monument in the Roman city of Hierapolis of Phrygia located in southwestern Anatolia. The aim of this study is to investigate the seismic behavior of this stone masonry structure using discrete element modeling. For this purpose, nonlinear dynamic analyses were performed to simulate the structural response of the gate under seismic excitation. Deformation, damage, and failure patterns induced in the masonry gate for different levels of seismic action are evaluated and discussed. An earthquake with a return period of 475 years is expected to cause some damage, but no collapse, while for a return period of 2475 years, the models indicate collapse of the monument. [ABSTRACT FROM AUTHOR]

Residual drift of structural systems after seismic events can make buildings uninhabitable and may cause their collapse in aftershocks, as seen in the 2023 Turkey-Syria earthquake. Self-centering rocking-core systems can eliminate plastic deformation of structures after earthquakes. In the current study, a bi-rocking steel-braced frame was designed using the modified modal superposition (MMS) method. The optimal location of the secondary joint was found to minimize the base shear, overturning moment, peak floor acceleration and inter-story drift. Damage to non-structural components has been considered. The models included 12-, 18- and 24- story frames that were subjected to far-field (FF), near-field-pulse (NP) and near-field-no-pulse (N) ground motion records. The seismic records were scaled to the maximum credible earthquake level. Nonlinear time-history analyses were performed using OpenSees open-source finite element software. Additionally, post-tensioned cables and energy dissipation fuses as variable parameters were optimized using particle swarm optimization. The performance of seven metaheuristic algorithms was compared and the results showed that placing the secondary joint at the mid-height of the structure reduced all seismic demand. The results also suggest that the story moment and FF records were most sensitive to the location of the secondary joint. It was observed that frames with lower stiffness and yield strength of the damper exhibited better seismic performance. Based on this, corrective percentages have been proposed for the design of the cable and dampers. A self-centering ratio of 1.07 was suggested at the mid-height and 1.19 for the base damper. The colliding bodies optimization algorithm performed best for time-history analysis-based optimization. • Using a bi-rocking mechanism to reduce the higher mode effects of high-rise structures. • Designing the bi-rocking steel-braced frame with modified modal superposition method. • Optimization of the main design parameters of bi-rocking joints using metaheuristic algorithms. • Investigating the performance of the bi-rocking steel-braced frame under far- and near-field ground motions. [ABSTRACT FROM AUTHOR]

In this study, risk assessment of 1-story precast building is conducted in probabilistic manner by using damage probability matrices (DPMs). Peak ground velocity (PGV) is used as reference ground motion parameter to associate with structural damages and more than three hundred real earthquake records is used for nonlinear dynamic analysis of precast buildings. Three different probabilistic calculation approaches mainly based on analytical methods have been used to obtain DPMs and utilized methods are compared. Comparisons have shown that analytical methods presented herein can be used to describe the upper and lower bound of damage probabilities of precast buildings, respectively. Evaluations on the damage probabilities have also pointed out that the structural differences among the buildings, use of different probabilistic approaches and damage ratios related with structural damage costs cause remarkable differences between the damage predictions and they can be considered as primary sources of uncertainties. Logic tree method, which has ability to gather involved uncertainties, is used to carry out reliable damage assessment. Results have shown that damage ratios of precast buildings determined after logic tree analysis have a good agreement with site investigation studies of 1999 Kocaeli earthquake occurred in Turkey and presented methods can be used in risk assessment of precast industrial buildings. [ABSTRACT FROM AUTHOR]

A seismic performance assessment of historical Kütahya Kurşunlu Mosque in Turkey is presented before and after it has been retrofitted. Site investigations were carried out to identify structural conditions, in which severe cracks, especially on the dome, were mapped. Regarding damage conditions, the Mosque has undergone several interventions, including retrofitting actions, in order to improve its seismic performance and global structural behavior. Effectiveness of seismic retrofitting of the Mosque was investigated by using the finite element method. Two representative structural models of the Mosque, namely non-retrofitted and retrofitted, were generated as a three-dimensional finite element model using an advanced structural analysis software. Ambient vibration measurements were performed to identify modal properties of the Mosque. Thus, the finite element model was calibrated and improved according to the experimental modal data. Nonlinear pushover and dynamic analyses were conducted to evaluate the seismic performance of the historical Mosque. This paper aims to demonstrate the effectiveness of the adopted retrofitting by comparing the models (before and after retrofitting) and, also, to validate the nonlinear behavior of the model by comparing it with the existing damage on the Mosque. [ABSTRACT FROM AUTHOR]

The present study aims to provide a comparative analysis between discontinuous models (DM) and continuous models (CM) for the analysis of majestic masonry structures subjected to seismic events. Specifically, the study models the 'Santa Maria Annnuziata' church damaged after the Central Italy earthquake sequence in 2016 and 2017 years. The DM is evaluated using different types of interaction laws between blocks: the Discrete Element Method (DEM) and the Non-Smooth Contact Dynamic method (NSCD). The nonlinearity of the material in the CM, instead, is considered using the Concrete Damage Plasticity model (CDP). To assess the models' effectiveness in identifying vulnerable elements, non-linear dynamic analysis is performed through the main earthquake events recorded nearby the church during the Central Italy earthquake. Following this, the models are subjected to the 7.8- magnitude earthquake that occurred in February 2023 in Turkey to observe the damage evolution under higher magnitude events. The primary objective of this study is to improve the understanding of the strengths and weaknesses of both models and their potential applications in the analysis of historic masonry structures. [ABSTRACT FROM AUTHOR]

Local geological conditions generate significant amplification of ground motion and concentrated damage during earthquakes. The highly concentrated damages at the edges of the Dinar basin during occurred earthquakes at regions close to rock outcrop bring up the effect of the inclined bedrock effect on the dynamic behavior of the basin with 2D geometry. In this study, first the idealized 2D model of the basin based on the results of the underground explorations and geologic investigations is proposed. Results show that Dinar basin has an asymmetric 2D geometry with two different bedrock angles at edges. Then, a numerical study using finite difference based nonlinear code which utilizes appropriate static and dynamic boundary conditions, and includes hysteresis damping formulation based on the user defined degradation curves is conducted using real earthquake motions of different strength and frequency content. The constructed model is subjected to the collection of 16 earthquakes with different PGA's of 0.1, 0.2, 0.3 and 0.4 g, four motions for each PGA. It was seen that the dynamic behavior of the basin is broadly affected by the two dimensional bedrock. The results indicates the higher effect of the 6° bedrock inclination at east part on the amplification with respect to the steeper 20° bedrock slope at the west. Also, the results show the insignificant effect of the bedrock at the depth more than 150 m on the amplification of the east edge. While the effect of the 6° bedrock angle at the east part continues until 1500 m from the outcrop, it affects the amplification until 700 m from the outcrop at the west part with 20° bedrock angle. [ABSTRACT FROM AUTHOR]

The soil 222Rn concentration non-linear patterns are investigated by the application of various chaos methodologies based on 70 272 measurement data from the East Anatolian Fault Zone, which is one of the world's most active faults. Among these methodologies are Lyapunov exponent, surrogate data, rescaled range (R/S) analysis, Fourier spectrum, phase space reconstruction, mutual information, false nearest neighbors, and correlation dimension. The results indicate that the nonlinear dynamical approach is convenient for characterization and prediction of the 222Rn concentration dynamics, which are in turn usually used as an earthquake precursor. Behaviour of 222Rn gas is important in earthquake prediction researches. [ABSTRACT FROM AUTHOR]

In January 2017, collapses of the numerous roofs were reported due to excessive snowfall in many provinces of Turkey. In this study, the reasons behind the collapses of the steel roofs of 19 factory buildings were investigated. The steel roofs supported by the precast reinforced concrete columns indicated a similar collapse pattern to each other under the unexpected heavy snow loading. The failure mechanisms of the roofs under the snow loading were simulated numerically. Nonlinear finite element models of a typical industrial building were developed and analyzed under an incremental vertical loading that is identical to snow loading. As a result of the analysis, the vertical load carrying capacity of the roof system and the snow load level causing the collapse of roof were determined. The resulting snow load was compared with the snow load values provided by the code specifications. In addition, the collapse mechanism of the steel roof system was analytically determined and compared with the collapse modes observed in the field and the causes of the failure were evaluated. The failure mechanism and the buckling modes obtained from analyses were found very similar to those observed during the site inspections. The main reasons of the roof failures may be attributed to excessive amount of snow caused by climate change and discrepancy of designed project and as-built project due to lack of building inspection control during the construction of the buildings. [ABSTRACT FROM AUTHOR]

This study presents forecast of highway casualties in Turkey using nonlinear multiple regression (NLMR) and artificial neural network (ANN) approaches. Also, the effect of railway development on highway safety using ANN models was evaluated. Two separate NLMR and ANN models for forecasting the number of accidents ( A) and injuries ( I) were developed using 27 years of historical data (1980-2006). The first 23 years data were used for training, while the remaining data were utilized for testing. The model parameters include gross national product per capita (GNP-C), numbers of vehicles per thousand people (V-TP), and percentage of highways, railways, and airways usages (TSUP-H, TSUP-R, and TSUP-A, respectively). In the ANN models development, the sigmoid and linear activation functions were employed with feed-forward back propagation algorithm. The performances of the developed NLMR and ANN models were evaluated by means of error measurements including mean absolute percentage error (MAPE), mean absolute error (MAE), root mean square error (RMSE), and coefficient of determination ( R). ANN models were used for future estimates because NLMR models produced unreasonably decreasing projections. The number of road accidents and as well as injuries was forecasted until 2020 via different possible scenarios based on (1) taking TSUPs at their current trends with no change in the national transport policy at present, and (2) shifting passenger traffic from highway to railway at given percentages but leaving airway traffic with its current trend. The model results indicate that shifting passenger traffic from the highway system to railway system resulted in a significant decrease on highway casualties in Turkey. [ABSTRACT FROM AUTHOR]

In Turkey, majority of industrial facilities are composed of precast buildings. However, precast buildings have suffered extensive damage during Kocaeli and Duzce (1999) and Adana-Ceyhan (1998) earthquakes. Therefore, in this study, fragilities of existing building stock and damage probabilities of precast buildings were studied. For this purpose, building inventories were prepared and variation of structural parameters was determined by investigating the design project of 65 precast buildings constructed in Denizli, Turkey. Twelve analysis models which reflect the stiffness, strength and ductility properties of building inventory were constructed. After the definition of strain based displacement limits and corresponding damage states for buildings, displacement demands were calculated by using non linear time history analysis. During the analyses 360 strong ground motion records were used. Exceedence ratios of concerned damage limits was calculated by checking the displacement demands and then PGV based fragility curves were constructed. Efficiency of strength, stiffness and ductility properties of existing precast buildings were investigated by comparing the fragility curves. The results have shown that the most effective parameters that govern the damage probabilities of precast buildings are stiffness and ductility. It was also stated that the results of fragility analysis and damage and failure observations performed after Kocaeli and Duzce Earthquakes are compatible. [ABSTRACT FROM AUTHOR]

The capacity curves of various structural systems that are used in the HAZUS methodology to determine seismic vulnerability were developed based on the seismic design codes. These capacity curves are, therefore, very idealistic and do not take into account variations in the regional design practice. This article presents the results of nonlinear static analyses of representative reinforced concrete frame buildings located in Turkey to obtain their capacity curves. A representative set of buildings was selected from existing RC buildings. The parameters such as yield over-strength ratio, fundamental period, post elastic stiffness, yield and ultimate drift ratios, and yield base shear coefficient have been obtained from the idealized capacity curves. These parameters are used in HAZUS to determine seismic response of buildings under a given hazard level. This seismic response is then used in predetermined fragility curves to estimate the expected loss for the particular building type. The capacity curves developed herein for Turkish buildings were compared with other studies and HAZUS recommendations. [ABSTRACT FROM AUTHOR]

• Incremental Dynamic Analysis for seismic assessment of masonry arch bridges in 3D. • Comparison of nonlinear static and dynamic analyses results. • Effects of the higher vibration modes of the structure in the response. • Interaction of the horizontal and vertical components of earthquake records. Masonry arch bridges form a noteworthy portion of road and railway networks in Europe and Turkey. Structural assessment of such bridges is often required because of their vulnerability to seismic actions. However, there are no standardized or widely accepted procedures, and the available assessment methods comprise significant uncertainties. This paper presents a seismic assessment of a stone masonry arch bridge using different methodologies by investigating the seismic behavior of masonry arch bridges and the uncertainties in the assessment methods presented. The Finite Element (FE) macro-modeling approach is used in modeling the behavior of the structure under investigation, after undertaking ambient vibration testing and dynamic identification study to determine the dynamic parameters of the structure. These experimental parameters were used to update the FE model before performing the seismic assessment using Nonlinear Static Analysis (NSA), Nonlinear Dynamic Analysis (NDA) and Incremental Dynamic Analysis (IDA). The IDA helped to depict the complete picture of the seismic behavior, whereas the comparison of the results highlighted the limitations of the NSA and enabled presenting recommendations for future work. In addition, the effects of the interaction of horizontal and vertical components of earthquake records in NDA underlined the necessity for their consideration in similar studies. [ABSTRACT FROM AUTHOR]

• A collapsed roof under heavy snowfall in Bozüyük Market in Turkey is investigated. • Snow loads for the national standards TS 498 and TS EN 1991-1-3 are compared. • Linear and nonlinear push-down analyses are carried out for different load cases. Heavy snowfall and frost are common phenomena in some areas of Turkey. Since it is an active seismic region, most engineering efforts focus on the impact of seismic loads. Meanwhile, the evaluation of structural and non-structural damages caused by snow loads are less of a concern. Depending on region geographical characteristics, snow is considered one of the most critical loads, especially in the case of large spans industrial structures, sport facilities and malls. This study investigates the snow induced failure of Bozüyük Market in Turkey. An evaluation of the attributed reasons behind the reported collapse is provided. To investigate the critical regions of the structural systems, a finite element model has been generated, linear and nonlinear static push-down analysis are carried out for the collapsed portion of the structure of interest. The snow load calculations are compared in regard to national standards TS 498 and TS EN 1991–1-3. It has been found that the construction defects were the primary reason behind the partially failure of the investigated roof. The paper highlights the urgent need to upgrade the national standards regarding snow loads to go along with the changes in snowfall density and frequency due to accelerated climate change. [ABSTRACT FROM AUTHOR]