Causes of the Earthquake in Turkey and the Consequences of the Colossal Destructive Impact

In February 2023, 2 large earthquakes occurred in the region of the East Anatolian Fault in Kahramanmarash (Turkey) – in Pazardzhik (M_w=7.7) and Elbistan (M_w=7.6) with an interval of 9 hours. In total, these earthquakes affected 11 cities and 15 million people: more than 46 thousand people died, more than 110 thousand people were injured, more than 100 thousand buildings were destroyed. In the first 17 days after these two earthquakes, 8032 aftershocks occurred, of which 424 were more than M_w 4. Peak ground accelerations that far exceed specifications during earthquakes: maximum peak horizontal acceleration (PGA) was 1.23 g, vertical ground acceleration was 1.09 g. The measurements taken at 250 earthquake stations in Turkey allow scientists around the world to conduct more accurate earthquake analysis. The main reasons for the destruction of buildings in Turkey as a result of seismic impacts are as follows: the enormous value of peak ground acceleration (PGA); proportionality of the horizontal and vertical components of the peak ground acceleration (ag horizontal = 1.23 g; ag vertical = 1.09 g); significant displacements of the ground base as a result of two earthquakes of magnitude M_w=7.7 and M_w=7.6 followed by 8032 aftershocks; unfavorable characteristics of the soil base; the desire of capitalist companies to maximize savings on design by using the labor of inexperienced engineers working in software complexes without a deep understanding of the methods of finite element analysis, design requirements, as well as design features in seismic areas; low quality control of construction production both on the part of capitalist companies and on the part of government agencies; the use of incorrect design solutions that do not provide reliability requirements taking into account construction in seismic areas, such as the use of frame systems without seismic insulation, transomless floor slabs of minimum thickness; low quality of materials in combination with low quality of concrete care; the use of smooth reinforcement in old projects (the required anchoring is not provided); violation of design requirements(both at the design stage and at the construction stage) in terms of the installation of transverse reinforcement in order to prevent buckling of longitudinal reinforcement, the perception of transverse forces and torques; the unpopularity of the use of passive seismic isolation in mass housing construction due to its high cost and limited service life; lack of reliable data on seismic zoning indicating maximum values of peak ground acceleration (PGA).

A. KOCHULU¹, Civil Engineer (This email address is being protected from spambots. You need JavaScript enabled to view it.);
D.A. KOCHULU², Civil Engineer (This email address is being protected from spambots. You need JavaScript enabled to view it.)

¹ Middle East Technical University (METU) (1, Dumlupinar Boulevard, 06800, University Quarter, Cankaya Ankara, 06800, Turkey)
² National Research Moscow State University of Civil Engineering (26, Yaroslavskoe Highway, Moscow, 129337, Russian Federation)

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