Sürdürülebilir Kalkınma Amaçları

  • MakaleAçık Erişim2025
    Changes of natural frequencies of masonry stone minarets due to temperature and humidity; [Yığma taş minarelerin doğal frekanslarının sıcaklık ve neme bağlı değişimleri]

    Aymelek, Abdullah; Yanık, Yusuf; Yıldırım, Ömer; Türker, Temel

    It is very important to distinguish the reason of change in natural frequencies of structures either caused by a possible damage or environmental conditions as temperature and humidity. In this study, the changes in the dynamic properties of masonry minarets under environmental effects such as temperature and humidity were investigated. The Minarets of İskenderpaşa, Hacı Kasım and Tavanlı Mosques in Trabzon were monitored by ambient vibration test method, the relationship between natural frequencies and temperature and humidity was tried to be determined. For this purpose, the natural frequencies of these minarets were measured at certain intervals under different temperature and humidity conditions over a period of approximately six months. The vibration measurement system which was developed by our research team was used in the measurements. From the data collected by these measurements, the variation intervals of the natural frequencies (the smallest and the highest values), the percentages of change and their relations with temperature and humidity were revealed. This relationship was determined by using linear-nonlinear simple and multiple regression analyses. From the study, it was found that the natural frequencies change under environmental effects such as temperature and humidity, and this rate of change was approximately 7%.

    • SDG 13 · İklim Eylemi
  • MakaleYalnız künye2023
    Full-scale structural evaluations of İskenderpaşa minaret

    Aymelek, Abdullah; Yanik, Yusuf; Demirtaş, Betül; Yildirim, Ömer; Çalik, İsmet; Türker, Temel

    Nowadays, innovative methods have been used for observing and structural evaluating of historical structures. In this paper, it is presented the full-scale structural assessments of a minaret after a Finite Element model calibrating according to vibration test results. Also, the structural behaviours under earthquake and wind loads were identified by considering the environmental effects on the selected masonry minaret of İskenderpaşa Mosque. First of all, modal analysis was executed on the three-dimensional Finite Element model created according to field survey in ANSYS Workbench. In-situ vibration tests were implemented at different intervals by using developed vibration measurement system. The experimental modal parameters were attained from collected signals. The experimental results were used as reference values in model calibration of this minaret to reflect the existing structural behaviour. Model calibration process was carried out on the initial model both by changing of material properties of masonry wall and by taking into account the interactions with mosque walls and ground. Full-scale structural evaluation was carried out under earthquake and wind loads on both the initial and the calibrated models in the weak direction of this minaret. The top displacements, drift ratios, principal stress values and their distributions were determined. It was shown that the analyses on the calibrated model produce more realistic structural behaviour.