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Sürdürülebilir Kalkınma Amaçları

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• MakaleYalnız künye2026/r/gumushane/13744
  Effects of earthquake frequency content and isolation thickness on seismic behavior of a structure system resting on geotechnical seismic isolation layer

  Ozturk, Kasif Furkan; Cakir, Tufan; Araz, Onur

  Geotechnical seismic isolation (GSI) systems aim to partially dissipate the energy before it reaches the foundation of the structure system and are therefore regarded as an important alternative to structural seismic isolation systems. In addition, the use of petroleum-derived waste materials in the GSI systems fills a significant gap in the field of waste recovery. The present study investigates the changes in the dynamic responses of a 5-story building system with and without GSI, using a set of earthquakes classified according to their frequency content. For this purpose, parametric analyses were performed using analytical methods, considering three different earthquake frequency contents and six different GSI thicknesses. Furthermore, an approach for selecting the GSI thickness was suggested. The results generally show that, for structures founded on both natural soil (NS) and GSI systems, the earthquakes with low frequency content produce responses greater than the average responses calculated for all the investigated earthquakes. Although increasing the GSI thickness has a significant effect on attenuating structural responses, increasing this thickness beyond 3 m does not lead to a relatively significant reduction in the dynamic responses of the investigated structural system. Therefore, considering the structural system, NS, rubber-soil mixtures and earthquakes examined in this study, selecting a GSI thickness in the range of 2–3 m (inclusive) may be regarded as a practical approach for mitigating the dynamic responses of the structure since further increments in thickness beyond this range provide only progressively limited improvements in structural responses. Consequently, this research may provide meaningful data for the development of vibration control strategies to improve seismic resilience of structures, and the results are expected to be useful for better understanding of the GSI applications.

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• BildiriYalnız künye2026/r/gumushane/13531
  Dynamic Analysis of a High-Rise Building Under Near-Fault and Far-Fault Loads Considering Soil-Structure Interaction

  Kaya, Dilek; Cakir, Tufan; Ozturk, Kasif Furkan

  Earthquakes that have occurred in our country and various countries around the world over the past 30 years have clearly indicated that the complex relationship between the soil, structure, and earthquake requires further research. This situation has shown that building behavior under dynamic loads can vary depending on parameters such as structural geometry, foundation soil system characteristics, and earthquake characteristics. Due to the fact that near-fault movements contain higher accelerations and higher velocity components compared to far-fault movements, high-rise structures may exhibit relatively more sensitive behavior under such loads and may be negatively affected by these earthquake contents. In this context, the aim of this study is to investigate the dynamic behavior of a 12-story building system under near-fault and far-fault ground motions, taking into account different soil properties. To this end, three-dimensional finite element models were first created for the 12-story building system, considering both fixed and flexible foundation conditions. Modal analyses were performed using finite element models created with ANSYS software, and the obtained mode periods were compared with those obtained from analytical models. Subsequently, the dynamic behavior of the 12-story building system was investigated using relative displacement, stress, and acceleration responses obtained from time-domain analyses conducted for different soil systems and fixed foundation conditions. Comparisons of the dynamic responses showed that the structural dynamic responses could be influenced not only by the soil-structure interaction system but also by nearby and distant fault earthquakes.

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• MakaleYalnız künye2025/r/gumushane/11755
  Assessment of Seismic Responses of Square-Hollow-Section Joints in a Lattice Girder with Soil-Structure Interaction

  Ozturk, Kasif Furkan; Ozyurt, Emre; Araz, Onur; Cakir, Tufan

  The fixed base approach is widely used to obtain the seismic behaviour of Square Hollow Section (SHS) joints in a lattice girder. However, in some cases where soil-structure interaction (SSI) can be relatively significant, this approach may result in incorrect acquisition of the natural periods and dynamic responses of the lattice girders using welded tubular joints. This situation may negatively affect the safety of the structure by causing an underestimation of the dynamic loads acting on the structure. Therefore, this study evaluates the seismic behaviour of SHS joints in a typical lattice girder exposed to different ground motions considering SSI. A nonlinear finite element analysis software, Abaqus, performs the dynamic analyses considering six earthquake excitations with three different frequency contents (a ratio of peak ground acceleration (PGA) to peak ground velocity (PGV)) and four different soil types. After verifying the numerical model, it is determined that 3D solid elements should be used to capture the actual seismic behaviour of the tubular joints in a steel truss frame with or without SSI. A comprehensive parametric study is then carried out to evaluate the peak displacement and stress values on the SHS joints with and without SSI under different ground motions with different PGA/PGV ratios. The findings show that the stresses are concentrated around the column and bottom chord connection region. Besides, the SSI mechanism significantly affects the peak stress and displacement values of the SHS joints, especially in soft soil types. Furthermore, it is observed that the PGA/PGV ratio significantly changes the seismic responses of the steel truss frame.

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• MakaleYalnız künye2025/r/gumushane/11720
  Effect of frequency content of ground motion on seismic response of buildings with variable aspect ratio including soil-structure interaction

  Kaya, Dilek; Cakir, Tufan; Ozturk, Kasif Furkan; Araz, Onur

  Soil-structure interaction (SSI) may lead to reduction, amplification or negligible change in structural responses depending on the relationship between the nature of excitations and subsoil conditions. Since neglecting SSI effects may cause uncertainties in seismic design, it is crucial to consider them during the design process. Another important factor affecting the dynamic behavior of structures interacting with the ground is the dynamic properties of the structures. To consider this effect, three buildings with 4, 8, and 12 stories designed in accordance with the Turkish Building Earthquake Code (TBEC-2018) are analyzed. The aspect ratios of these structures are 2, 4, and 6, corresponding to squat, ordinary, and slender structures, respectively. The primary objective of this study is to simulate the combined effects of these key parameters on the dynamic response of reinforced concrete structures. In the time history analyses, six ground motions classified by three different frequency contents are considered. 3D finite element models of SSI systems are established using ANSYS software. The usability of the numerical models is demonstrated for both SSI and fixed-base cases through three different analytical approaches. The displacement, acceleration, and stress responses are examined through time history analyses. The results indicate that the SSI is not negligible and neglecting the SSI is an oversimplification that does not lead to always-conservative predictions. Moreover, both the frequency content of the excitation and the structural aspect ratio are found to be decisive parameters in seismic response.

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• MakaleAçık Erişim2024/r/gumushane/14451
  Effect of Soil-Structure Interaction on Story Acceleration Response of a High-Rise Building

  Araz, O.; Ozturk, K.F.; Cakir, T.

  In this paper, the effect of soil–structure interaction (SSI) on the story acceleration response of a high-rise building due to different earthquakes is investigated. To determine the dynamic response of a 40-story building considering SSI, six different foundation soil conditions and ten different earthquake records are considered. The results show that the SSI effect on the story acceleration response of the high-rise building resting on relatively soft soil types is of critical importance.

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• MakaleYalnız künye2023/r/gumushane/14374
  Effect of foundation embedment ratio in suppressing seismic-induced vibrations using optimum tuned mass damper

  Araz, Onur; Cakir, Tufan; Ozturk, Kasif Furkan; Kaya, Dilek

  Tuned mass damper (TMD), which is used in structures to mitigate the dynamic responses caused by environmental loads, is tuned according to the dominant frequency of the structures. The dominant frequency of structure built on soil with low stiffness is significantly affected by the soil-structure interaction (SSI). In previous studies, only the surface foundation case is considered to investigate the design parameters of TMD considering SSI effects and the embedment depth of the foundation is neglected in these studies. Thus, this paper investigates the optimization of TMD for mitigation of responses of a high-rise building considering various depths of embedment and soil properties. The optimum parameters of TMD are investigated using five different optimization algorithms (i.e., simulated annealing, sequential quadratic programming, genetic algorithm, pattern search, and particle swarm optimization). The objective function minimizes the peak acceleration amplitude at the top of the structure. The effectiveness of optimum TMD is verified to use 20 near-fault pulse-like ground motions. The comparisons show that the embedment ratio of the foundation and the soil properties significantly affect the optimization of TMD.

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• MakaleYalnız künye2023/r/gumushane/12821
  Influences of Wall Configurations on Earthquake Behavior of Cantilever Retaining Walls Considering Soil-Structure Interaction Effects

  Ozturk, Kasif Furkan; Cakir, Tufan; Araz, Onur

  Cantilever walls are frequently and necessarily built not only in earthquake prone regions but also on different foundation subsoils with various physical and mechanical characteristics. The response of these structures is a complicated soil-structure interaction (SSI) problem, in which the relative stiffness between the soil and structure is of critical importance. In addition to different soil conditions and earthquake motions, the wall configurations have an important role in the cantilever retaining wall design. Thus, the major objective of this work is to investigate the effects of various configurations on seismic response of the cantilever retaining walls considering SSI. Accordingly, the seismic response of the interaction systems is revealed using the 3D finite element models (FEM) in time domain, assuming linearly elastic behavior for the wall, and elastoplastic behavior for backfill and foundation soil. Viscous absorbent boundaries are employed to both simulate radiation scenario and avoid undesirable wave reflections generated by soil lateral boundaries. Backfill-wall interfaces are modeled using the unidirectional interface elements with nonlinear force-deflection abilities. The interaction systems are analyzed considering three different cantilever wall configurations (inverted T-type, L-type, and the wall with a base key), four different ground motion records, and four different subsoil systems. Nonlinear seismic analyses are carried out to visit how considering the variation of these parameters influences the wall behavior. The results from parametric studies show that the wall configuration, SSI effects and ground motions are remarkably influential on seismic responses of the cantilever walls such as the stresses and horizontal displacements.

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• MakaleYalnız künye2022/r/gumushane/12698
  Effect of earthquake frequency content on seismic-induced vibration control of structures equipped with tuned mass damper

  Araz, Onur; Cakir, Tufan; Ozturk, Kasif Furkan

  The main goal of this paper is to investigate the influence of the earthquake frequency content on the optimization of tuned mass damper (TMD) for multi-story buildings. Earthquake frequency content is divided into three groups (i.e., low, intermediate and high frequency content) according to the ratio of peak ground acceleration to the peak ground velocities. Time-domain analyses are performed to obtain the dynamic responses of 10-story and 40-story shear buildings equipped with a TMD under twelve different earthquake records. Advanced firefly algorithm is used to obtain the optimum parameters of the TMD such as the frequency ratio and the damping ratio. The optimization criterion is selected as the minimization of the maximum top story displacement of the building with TMD. The optimum parameters of TMD designed by this paper and its control performance are compared with those of other previous works available in the literature. Compared to the other methods, the optimum TMD designed by this study especially performs better in reducing the maximum top story displacements. Furthermore, it is discussed why TMD is ineffective in reducing the maximum floor accelerations of 40-story building, and then the effect of different mass ratios and objective functions in reducing the maximum responses of both buildings under critical earthquake excitation is investigated in detail. The results also show that the frequency content of earthquake ground motions has a significant effect on the optimum parameters of TMD and its control performance.

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• MakaleYalnız künye2022/r/gumushane/12685
  A comparative study to determine seismic response of the box culvert wing wall under influence of soil-structure interaction considering different ground motions

  Ozturk, Kasif Furkan; Cakir, Tufan; Araz, Onur

  The present study deals with evaluation of the effects of different ground motions, backfill-structure interaction (BSI) and soil-structure interaction (SSI) on dynamic response of a box culvert wing wall. In obtaining numerical results, five different earthquake records with different frequency contents, five different backfill types and four different subsoil types are taken into account. Firstly, a finite element model (FEM) and three analytical models are proposed for analysis of the wing wall-backfill system under fixed-base case, and these fixed-base models are compared with each other through both modal analysis and displacement time-history analysis under the assumption of linear-elasticity. After validating the ability of the FEM approach, by extending the fixed-base FEM to take account of elastoplastic behavior of soil and SSI, a three dimensional (3-D) model has been described, and 3-D nonlinear analyses have been carried out in time domain. The numerical results show that the seismic response of the wing walls are affected remarkably by the SSI, BSI and frequency content of the earthquake.

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• MakaleYalnız künye2022/r/gumushane/11420
  Effect of different objective functions on control performance of tuned mass damper for a high-rise building considering soil–structure interaction

  Araz, Onur; Ozturk, Kasif Furkan; Cakir, Tufan

  This paper deals with the optimization of the tuned mass damper (TMD) with different objective functions for high-rise building under earthquake motions considering soil–structure interaction (SSI). A study is conducted to search for the TMD that outperforms five objective functions (i.e., OF-1–OF-5) containing combinations of the structural responses and foundation responses. The main goal of the present study is to evaluate and compare the control performance of these five objective functions. The optimum parameters of TMD are obtained by particle swarm algorithm (PSA) to minimize the acceleration transfer function. To determine the dynamic response of a 40-story building under the influence of SSI, six different foundation soil conditions and eight different earthquake records are considered. The results show that the SSI effects on the dynamic response of the high-rise building resting on relatively soft soil types such as SD and SE are of critical importance. It is shown that the effectiveness of the optimum TMD designed by OF-1 is better than the others in suppressing the peak response values for all soil types. After OF-1, the best performances are obtained for OF-3 and OF-5 which yield approximately the same effectiveness. It is also found that different earthquake records, soil types and objective functions are very effective on the effectiveness of TMD.

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