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Öğe An experimental evaluation on structural performance level of corroded reinforced concrete frames(Elsevier Sci Ltd, 2025) Turan, Ahmet Ihsan; Ayaz, Yasar; Yalciner, Hakan; Kumbasaroglu, AtilaA total of 5 full-scale Reinforced Concrete (RC) frames were tested to develop new models for predicting the structural behavior of corroded RC frames and to verify the accuracy of the models mostly developed for RC columns. Four corroded and one non-corroded RC frame were tested under cyclic loading. Corroded RC frames were tested under displacement-controlled cyclic loading at four corrosion levels and for a constant applied axial load ratio of 0.20, with the same concrete compression strength level and reinforcement bar layout. Actual corrosion ratios were obtained following the loading tests, breaking all RC columns and beams and extracting all reinforcement bars from concrete. The test results demonstrated that the corrosion level played an active role in the structural capacity of the RC frames. Initial corrosion crack widths had more significant effects on structural performance. Some models proposed for corroded RC columns can also be used for corroded RC frames in terms of yield and ultimate load capacities according to the corrosion levels of the columns and beam composing the RC frame. It was also concluded from the test results that the displacement-based ductility ratio for corroded RC frames could still be misleading if they were not computed according to energy-based or bilateral failure criteria. Structural properties such as initial/secant stiffness and energy absorption capacity calculated based on experimental measurements for RC frames had further disclosed corrosion effects.Öğe Assessments of Masonry Buildings and Historical Structures during the 2020 Sivrice-Elaz?? Earthquake(Budapest Univ Technology Economics, 2023) Ozmen, Alper; Maras, Muslum Murat; Ayaz, Yasar; Sayin, ErkutTurkey is located on a seismically active region. The active fault zones, primarily the North Anatolian Fault and East Anatolian Fault, constitute a center to the movements. On 24 January 2020 at local time 20:55, an earthquake of Mw = 6.8 struck Sivrice, Elazig located in eastern part of Turkey. After this main shock, 1185 aftershocks were recorded until February 8, 2020. The main event resulted in 41 human casualties and 1632 injured. Also, 45 people were salvaged from the debris. The earthquake mostly affected to Elazig and Malatya provinces. 633 buildings were demolished, 10492 buildings were severely damaged, 2161 buildings were moderately damaged, and 16046 buildings were slightly damaged in the affected region. This paper focus on evaluating the damages and failures of masonry, adobe, and historical structures in the affected areas around Elazig and Malatya provinces.Öğe Effect of slope in S-type adhesive bonding under axial loading(Springer Heidelberg, 2019) Ayaz, YasarContemporary industrial practice takes wide advantage of adhesive materials and adhesive bonding techniques, notably in the aviation and automotive industries. The geometry of bonded joints may vary considerably, and this paper explores the potential advantages of S-shaped lapped profiles with particular reference to the slope of the S. This aspect of the joint offers improvements in the area of adhering surfaces and provides superior bonding in comparison with conventional single lap joints. The study examines 30-mm overlapping specimen joints made from 100-mm-length by 25-mm-width AA 2024-T3 aluminium alloy sheets, having alternative thicknesses of 6.5, 10 and 13.5 mm. It also features three alternative radii for the profiles, thus generating different slopes for the S-shapes. The specimen joints were bonded using acrylic adhesive DP 810, modelled using finite element analysis and subjected to physical confirmation of the analysis results. The results show that a decrease in profile radius correlates with an increase in failure load; that an increase in profile radius lessens the effect of thickness on damage load and that bending moment is absent from the adhesive bonding profile of the S-shape.Öğe Experimental evaluation of reinforced concrete columns produced with natural perlite aggregates under cyclic loading(Wiley, 2026) Atli, Sefa; Yalciner, Hakan; Kumbasaroglu, Atila; Ayaz, Yasar; Turan, Ahmet Ihsan; Bulut, H. Alperen; Naimi, SepantaA total of four reinforced concrete (RC) columns were tested to compare the structural capacities of RC columns produced by natural perlite aggregates and conventional concrete. The structural performance of the RC columns made from natural perlite aggregates was compared to conventional RC columns regarding the same concrete strength levels, sectional properties, and reinforcement layouts of conventional RC columns. The RC columns were tested under a combined constant axial load ratio of 30% with cyclic loading for two concrete strength levels, namely, 25 and 40 MPa. Load-displacement curves, energy absorption capacities, stiffness degradation, the moment-curvature relationship, the plastic hinge mechanism, and the ductility index were experimentally obtained at two different concrete types along with the measured stress-strain properties of the conventional and perlite concrete. The test results showed that the construction of the RC columns using only perlite may become possible in the future by providing an adequate concrete stress-strain capacity, which will be improved. Additionally, the use of natural perlite aggregates can contribute to sustainable construction practices by reducing the reliance on conventional aggregates.Öğe Mechanical behavior of butt curved adhesive joints subjected to bending(Walter De Gruyter Gmbh, 2021) Ayaz, Yasar; Citil, SerifFactors such as the surface geometry of a joint, the direction of the applied load, and the type of adhesive used have a great influence on the strength of a joint in adhesive bonding. In adhesively bonded joints (ABJ), it is possible to improve surface geometry by forming various geometric surfaces. ABJs are not very resistant to peeling stress, thus requiring that a bonding model be analyzed according to the direction of the applied load to prevent peeling stress. In this study, a butt curved joint was prepared from aluminum plates (A2024-T3) to improve the surface geometry of the joint. The mechanical behavior of the joints in three-dimensions and subjected to bending were investigated depending on an increase in the curvature radius. The adhesive DP810 was used for bonding. The finite element analysis was performed in ANSYS and cohesive zone modeling was used for a simulation of the damage growth in the adhesive layer. The results of bilinear and exponential models were found to be more appropriate to the experimental results. When the radius of curvature increases, the damage load carried decreases in the butt curved lap joints. It was seen that decreases in the curvature radius significantly decrease normal stress.Öğe Modeling of compressive strength and UPV of high-volume mineral-admixtured concrete using rule-based M5 rule and tree model M5P classifiers(Elsevier Sci Ltd, 2015) Ayaz, Yasar; Kocamaz, Adnan Fatih; Karakoc, Mehmet BurhanCompressive strength and UPV parameters are the methods that are used to determine high-volume mineral admixture concrete quality. But experiments for all levels of these parameters are expensive, difficult and time consuming. For determination of output values, classifiers with model extraction features can be used. In this study, classifiers, with the rule-based M5 rule and tree model M5P in the area of data mining are used to predict the compressive strength and UPV of concrete mixtures after 3, 7, 28 and 120 days of curing. The M5 rule and tree model M5P are tested using the available test data of 40 different concrete mix-designs gathered from literature [1]. The input of the model is a variable data set corresponding to concrete mixture proportions. The findings of this study indicated that the M5 rule and tree model M5P models are sufficient tools for estimating the compressive strength and UPV of concrete. 97% and 87% success is obtained in predicting compressive strength and UPV results, respectively. (C) 2015 Elsevier Ltd. All rights reserved.Öğe Predicting the effect of adherend dimensions on the strength of adhesively bonded joints using M5P and M5 classifiers(Springer Heidelberg, 2020) Ayaz, YasarThe configuration of adhesive bonding, especially adhesive-adherent interface, is very important in adhesive bonding. Adherend thickness, overlap length and adherend width have a great effect on failure load. It is important to know the effect of these parameters in the estimation of failure load. In this study, two models based on data mining techniques were generated for the estimation of the effect of adherend thickness, width and overlap length on failure load in adhesively bonding joints. One of the models is based on the M5P model tree and the other is based on the M5 rule algorithm. Experimental data were used to evaluate the performance of the models. The correlation coefficient parameter was used to compare the models' performance. The evaluated correlation coefficient is 93% for the M5P model tree and 96% for the M5 rule.Öğe Prediction of compressive strength and ultrasonic pulse velocity of admixtured concrete using tree model M5P(Ernst & Sohn, 2020) Kocamaz, Adnan Fatih; Ayaz, Yasar; Karakoc, Mehmet Burhan; Turkmen, Ibrahim; Demirboga, RamazanThe quality of concrete was assessed based on measurements of ultrasonic pulse velocity (UPV) and compressive strength. Portland cement (PC) was substituted with silica fume (SF), fly ash (FA) and blast furnace slag (BFS) as mineral admixtures. The compressive strength and UPV of concrete mixtures were estimated with classifiers alongside the tree model M5P in the data mining field. The compressive strength and UPV were modeled as a function of five input variables: day, cement, SF, FA, and BFS. It was found that UPV and compressive strength had an exponential correlation with SF, FA, BFS, SF + FA, SF + BFS and FA + BFS. However, additive-free admixture and PC-free substitution levels had a different constant in empirical work. According to the results obtained, both compressive strength and UPV of concrete mixtures could be reliably anticipated with the tree model M5P in a proportion of 97%. Hence, this model could be a potential new method for modeling mineral admixture concrete.Öğe Prediction of seismic performance levels of corroded RC frames based on crack width(Elsevier Science Inc, 2025) Turan, Ahmet Ihsan; Kumbasaroglu, Atila; Yalciner, Hakan; Ayaz, YasarIn reinforced concrete (RC) structures, corrosion of the reinforcement due to environmental factors or concrete components poses significant risks to both structural integrity and safety. Reinforcement corrosion, can be visually detected through cracks in the concrete cover, and this situation offers a practical approach to associating corrosion-induced cracks with structural parameter degradations caused by the corrosion mechanism. In this study, a total of five RC frame specimens were fabricated, with one specimen not exposed to corrosion and four specimens exposed to different levels of corrosion through the accelerated corrosion method, all having the same cross-section and material properties. In the experiments conducted under a constant 20 % axial load and cyclic repeated load effects, the structural performance indicators of the RC frame specimens were examined. Within the scope of the study, two experimental models are proposed. The first model aims to estimate the loss in the cross-sectional area of the reinforcement bar based on crack width, while the second model was oriented towards estimating the energy consumption capacity of the specimen for a specific displacement ratio based on the loss in the cross-sectional area of the reinforcement. The results revealed that as the corrosion ratio increased, the crack widths of the specimens also increased, and after a 1.5 % drift ratio, there was a significant decrease in the energy consumption capacities of the corroded specimens.Öğe Seismic Assessment of the Historical Sutlu Minaret Mosque(Budapest Univ Technology Economics, 2022) Maras, Muslum Murat; Ozmen, Alper; Sayin, Erkut; Ayaz, YasarHistorical masonry structures that connecting the past to the present have great importance because they represent the experiences and characteristics of various cultures. Therefore, the protection of historical structures is important. In this study, the structural response of the historical masonry Mosque was evaluated through dynamic analyses. For this purpose, the Sutlu Minaret Mosque which is located in Malatya, Turkey, was investigated. The three-dimensional model of the historical mosque was generated with ANSYS software. The material properties of the mosque were obtained with experimental tests. The time history analyses were used to obtain the seismic behavior of masonry mosque. In the time history analyses, six different strong ground motion records, including the 2020 Elazig earthquake, were used. After the analysis, displacement and stress values in the mosque were given. The absolute peak displacement value among these earthquake records was obtained from the 1999 Duzce earthquake and the highest principal compressive and tensile stress values were determined for the 2010 Darfield earthquake. Also, the crack regions which occurred in the mosque after the 2020 Elazig earthquake were compared with the dynamic analysis result of the 2020 Elazig earthquake. The crack regions formed after the Elazig earthquake are similar to the possible crack regions formed after the dynamic analysis.Öğe Stress analysis of adhesively bonded double strap joints with or without intermediate part subjected to tensile loading(Taylor & Francis Ltd, 2017) Citila, Serif; Ayaz, Yasar; Temiz, SemsettinAccidents in the industry, especially in the field of aerospace, are quite common. Damages like tears cracks and holes occur especially when small sand particles present in the airfield collide with the body and wings of an airplane during takeoff and landing. This torn, cracked, or pierced region should be repaired gently. Damaged parts are frequently small regions for which repair is more suitable than complete replacement as workmanship; cost and time are an important concept in today's world. A gap occurs between the patches if double-bonded patches are used in the repair of the damaged parts. In this study, the region between patches in a joint with and without intermediate parts was modeled and its effect on strength was examined numerically and experimentally. The effects of patch thickness, overlap length, adherent thickness, and gap length on the strength of the joints with and without intermediate part was compared. The results show that the intermediate part does not have any influence on the strength of the lap joint such that double strap joints without intermediate part have higher failure load. Additionally, it is seen that the failure load decreased with increasing patch thickness and increased with the thickness of the adherent.Öğe The effect of elevated temperature on the mechanical properties of concrete produced with raw perlite aggregate(Elsevier, 2026) Ozturk, Akif Berke; Turan, Ahmet Ishan; Kumbasaroglu, Atila; Yalciner, Hakan; Ayaz, YasarDeterioration caused by elevated temperatures in the micro- and macrostructure of concrete can lead to significant reductions in its mechanical performance, making it crucial to assess the residual behavior of concrete elements after thermal exposure. This study experimentally investigates the effects of elevated temperatures (25 degrees C, 200 degrees C, 400 degrees C, and 600 degrees C) on cubic and prismatic specimens produced with two different aggregate types (raw perlite aggregate and conventional coarse aggregate) across four mixtures (C25, C40, P25, and P40). Destructive (compressive and flexural strength) and non-destructive (ultrasonic pulse velocity, scanning electron microscopy) tests were conducted before and after thermal loading. Increasing the temperature to 600 degrees C reduced the compressive strength of conventional mixtures by 34.91 % (C25) and 41.79 % (C40), whereas perlite-based concretes exhibited significantly lower reductions of 9.91 % (P25) and 12.80 % (P40). Mass loss remained negligible (<2 %) up to 200 degrees C, increased to 4-6 % for conventional mixtures and 6-11 % for perlite-based mixtures at 400 degrees C, and reached 25-40 % and nearly 47 %, respectively, at 600 degrees C. UPV results revealed a substantial degradation in internal integrity at high temperatures, with decreases of 49-60 % in conventional concretes and only 16-17 % in perlite-based mixtures at 600 degrees C. Although the flexural strength of P25 and P40 was initially lower at 25 degrees C, their post-heating performance became comparable to conventional mixtures, showing similar residual flexural behavior at elevated temperatures. SEM observations further confirmed that perlite-based concretes exhibited fewer microcracks and reduced matrix deterioration compared to conventional mixtures. Overall, the findings clearly demonstrate that raw perlite aggregate significantly enhances the thermal resistance, internal stability, and residual durability of concrete, making it a promising sustainable alternative for structures exposed to elevated temperature environments.
