Sürdürülebilir Kalkınma Amaçları

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• MakaleYalnız künye2026Scopus SJRQ2/r/bayburt/11398
  Frequency-Based Damage Detection with ANN and Seismic Behaviour Assessment of a Historical Masonry Tower

  Demirtaş, Betül; Türker, Temel; Yanik, Yusuf; Dede, Tayfun

  Nowadays, Artificial Neural Networks (ANNs) are widely used in damage detection because of their powerful computational and exceptional ability to recognize patterns in historical structures. This paper presents the seismic behaviour assessment and structural damage detection performance of the ANN trained with natural frequencies to identify the damage on the Hagia Sophia Bell Tower in Trabzon, Türkiye. Reduction in the stiffness of the structures causes changes in the structural dynamics. Natural frequencies, being key indicators in damage detection, were utilized as input parameters to train the ANN in this study. The study’s scope included updating of the initial finite element (FE) model constituted with SAP2000 software according to the experimental dynamic characteristics obtained from the Civil Engineering Vibration System developed by our work team. The seismic behaviour of the tower was also examined through time history analyses under the effect of strong earthquakes. The required data for the ANN analyses was obtained from the FE modal analysis of the tower. The ANNs dataset was generated separately by simulating both single and double damage scenarios. Possible twelve damage zones were determined according to the places where the highest stresses occurred in the earthquake analysis of the tower. The reduction in the elasticity modulus of each region defined on the tower was considered as damaging effect and used as ANN output parameter. It was shown that ANN trained with natural frequencies can effectively identify the location and severity of damage.

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  AtıfScopus6·OpenAlex7

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• MakaleAçık Erişim2025Scopus SJRQ2/r/bayburt/11125
  Bending and Buckling Analysis of Porous 2D Functionally Graded Beams with Exponential Material Property Variation

  Adiyaman, Gökhan; Turan, Muhittin

  The bending and buckling analysis of porous two-directional (2D) functionally graded (FG) beams was conducted using a higher-order shear deformation theory. The introduction of exponential functions to depict changes in material properties is a novel approach in the static analysis of 2D FG beams. Three distinct porosity distribution functions were taken into account. The governing equations were formulated through the application of Lagrange’s principle. During the numerical analysis, a finite element comprising two nodes and eight degrees of freedom was utilized. This choice facilitated accurate and efficient solutions, even for shorter beams, without the need for a shear correction factor. Notably, the obtained shear stresses aligned with actual values, registering as zero at both the top and bottom of the beam. The obtained results of the study were validated against findings reported in the literature. A parametric study was carried out to investigate the effects of porosity, porosity distributions, gradation parameters, slenderness, and boundary conditions on the non-dimensional deflections, stresses, critical buckling loads, and buckling mode shapes. It was found that both porosity and the distribution of porosity have noticeable effects on the static analysis of the beams.

  AtıfScopus18·OpenAlex13

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• MakaleYalnız künye2024Scopus SJRQ2/r/bayburt/12860
  Optimization, Characterization, and Carbon Footprint Analysis of Alkali Activated Waste Tuff and Fly Ash Mixtures for Deep Mixed Columns

  Kamiloğlu, Hakan Alper; Yilmaz, Fatih

  Deep soil mixing (DSM) applications are one of the widely known soil stabilization techniques which can be applied to a wide range of soil types. Cement and lime are the major materials used as binders for DSM applications. However, as conventional binders lead to emit a large amount of CO2 during production, eco-friendly binders suitable for DSM applications have become prominent. Alkali-activated materials are good alternatives to conventional binders. This study was intended to investigate the usability of zeolite rich tuff wastes as an alkali-activated binder in DSM columns. Within this scope, the waste tuff and C-type fly ash mixture were used as an alkali-activated binder, and 10 M NaOH solution was used as an activator. Response surface methodology (RSM) was employed in experimental design to determine optimum components to obtain maximum unconfined compression strength and investigate the interaction between stabilization agents. From the RSM analysis the optimum ratios of activator (X1), waste tuff (X2), and precursor (X3) were determined as; X1 = 0.251, X2 = 0.548, and X3 = 0.538 for maximum UCS. UCS, mineralogical and microstructural characterization (XRF, XRD, SEM, EDX, FTIR) was performed for the DSM samples prepared considering the optimized components. It was determined that the UCS values of the 3, 7, and 28-day cured samples stabilized by considering the optimum values gave UCS values approximately 3 to 5 times higher than the lower limit values recommended by FHWA. As a result of mineralogical and microstructural investigation, the reason for the strength increase in the samples can be attributed to the formation of geopolymeric gel between the soil particles by tuff waste and fly ash activated with alkaline activator. Carbon footprint analyses were performed for 1m3 DSM columns produced with alkali-activated binders and ordinary Portland cement (OPC). From the analyses it was seen that the carbon footprint of the DSM column produced using alkali activated binders is lower than that of the DSM column obtained with OPC. After the general evaluation of the study, it is seen that the hypothesis that waste tuff can be used as environmentally safe alkali-activated binders instead of traditional binders is supported.

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  AtıfScopus6·OpenAlex6

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• MakaleAçık Erişim2022Scopus SJRQ3/r/bayburt/12188
  An Investigation of the Effect of Curing Temperature on the Deformation Characteristics of the Stabilized Soil Layers Treated with Lime and Tuff Wastes with Response Surface Method

  Kamiloglu, Hakan Alper; Turan, Huseyin

  The shallow spread foundations are one of the widely used foundation types for low-rise, low-cost or commercial buildings. However, it is not possible to use this type of foundation for soils with low bearing capacity or capable of excessive settlements. In these cases, stabilized soil layers overlying insufficient soil may be alternative to the high-cost foundation systems. As the temperature of the soils depends mostly on air temperature for shallow depths, curing conditions of the stabilized soil layers are affected by the air temperature. The effect of curing temperature on the pressure-settlement relation of the layered soil is a gap in the literature. This study investigates the effect of Bayburt tuff on pressure-settlement characteristics of layered soil for various curing temperatures. The specific objectives of this paper are to (1) examine the effect of using the waste tuffs as a stabilization agent in layered soils, (2) evaluate the usability of response surface methodology (RSM) to estimate shear strength parameters (c, ϕ), unconfined compression strength, and secant modulus of the stabilized soil with less experiment, (3) investigate the effect of dimensions of the stabilized soil block (length, with and thickness) on pressure-settlement relations under various curing temperature (T = 3 °C, 13 °C, 23 °C, 33 °C, 43 °C). This study comprises experimental and numerical parts. In the experimental part, strength parameters (c, ϕ) and secant modulus of stabilized soil samples were estimated with response surface methodology for various curing temperatures (3 °C, 23 °C, 43 °C). The effects of curing temperature on shear strength and Bulk’s modulus parameters were determined with the derived RSM model. In the numerical part of the study plate load test was simulated with the derived 2D axisymmetric FE model. The parameters required for the FE analyses were determined with the derived RSM model. As a result of the study, it was seen that it is possible to estimate experimental parameters accurately using the RSM approach with fewer tests. Bayburt tuff and lime mixtures increase the stiffness of the layered soil. The curing temperature has considerable effects on the pressure-settlement relationship up to a certain value. After a certain value increasing curing temperature has no considerable effects on the stiffness of the layered soil.

  AtıfScopus3·WoS1

  İncele
• MakaleYalnız künye2022Scopus SJRQ3/r/bayburt/11811
  Comparison of Statistical Methods to Graphical Method in Precipitation Trend Analysis, A Case Study: Coruh Basin, Turkey

  Hırca, Tuğçe; Eryılmaz Türkkan, Gökçen

  It is a known fact that the precipitation characteristics will become irregular as a result of climate change resulting from global warming. Trend analysis is one of the most effective methods of observing the effects of climate change on precipitation. This study compares the changes in precipitation with traditional trend analysis methods and graphical method (divided into subcategories using the Z-Score Index). Some preliminary analyzes (missing data estimation, homogeneity check, autocorrelation, and removal of the autocorrelation), which are lacking in many studies in the literature, have been performed. In this context, the monthly total precipitation data of the precipitation stations belonging to the Coruh Basin, one of the most important basins of Turkey, for the period 1972–2011 were used. As a result of the study, it was determined that all the stations’ data were homogeneous, and 92% of them were at the Class A level. While 100% trend is determined in Innovative Trend Analysis in total annual precipitation, this rate was just 40% at Mann–Kendall and Spearman's rho at 95% confidence. An increasing trend was determined in the “high” group of total spring precipitation at all stations.

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  AtıfScopus5·WoS4·OpenAlex5

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