An important research on the determination of natural vibration periods of minarets has been published

Altınbaş University Department of Civil Engineering faculty member Prof. Dr. Aykut Erkal and graduate student Zahraa Husham Ibrahim Hilmi have developed new relations that help determine the first four natural vibration periods of mosque minarets. Prof. Dr. Aykut Erkal also stated that his research, which will shed light on future studies in the fields of earthquake engineering and the protection of historical buildings, was published in the internationally prestigious Elsevier journal “Structures”.

Important contribution to science and engineering

Prof. Dr. Aykut Erkal explained that with this study, they aimed to make an important contribution to the conservation of historical and modern minarets by determining their dynamic behavior parameters in the light of their material and geometric properties. The developed relations will help engineers and researchers to quickly and efficiently determine the vibration characteristics of minarets.

Dynamic behavior of minarets can be evaluated significantly

Stating that mosque minarets are structures of great architectural, historical, religious and social importance, Prof. Dr. Aykut Erkal said that they can be noticed even from far distances thanks to their thin and long structural forms. He explained that especially historical minarets are mostly built of brick and cut stone and adorned with detailed ornaments. However, he underlined that these structures can vibrate under dynamic loads such as earthquakes due to their delicate forms. Noting that the period of a minaret is the round trip time of the minaret at the moment of vibration, Erkal said that this is a critical parameter both in the evaluation of existing structures and in the design of new structures to be built.

Determining the periods of minarets

Prof. Dr. Aykut Erkal from Altınbaş University stated that the natural vibration period of a minaret can be determined by three different methods:

1. Experimental methods: The period can be determined by on-site measurements. However, this method is costly and may not be practical as it requires special equipment and official permission.

2. Mathematical modeling: The period can be calculated by computer-aided modeling. However, this method requires computers with high processing power, personal effort and time.

3. Empirical formulas: Although they give approximate results, they offer a practical, economical and fast solution.

Newly developed relations...

Prof. Dr. Aykut Erkal and Zahraa Husham Ibrahim Hilmi conducted extensive analyses by creating a mathematical model of 189 minarets with different geometries and material properties. Using iterative optimization analysis, the academics developed 4 relations with 5 and 3 variables that give the first four natural vibration periods of the minarets. The relations proposed in the study were tested on 35 different minarets, whose dynamic properties were previously determined experimentally, and the results obtained were found to be highly satisfactory. In particular, the 5-variable relation that calculates the first period was found to give accurate results in 28 of the 35 minarets with differences much less than 19%. Accordingly, Aykut Erkal stated that engineers can use these relations to have an approximate idea of whether the minarets are at risk in a specific earthquake.