*4.1. Comparison of Natural Fundamental Periods*

In this part, the period values obtained according to the eigenvalue analyses were compared with the empirical ones predicted for each country. The time required for the undamped system to complete one vibration cycle is called the natural vibration period of the system. The more rigid one of the same mass with a single degree of freedom system will have a shorter natural period and a higher natural frequency. Similarly, of two structures of the same stiffness, the heavier (greater mass) has a lower natural frequency and a longer natural period. This value can be obtained both with approximate formulas and as a result of numerical analysis [143–146]. The empirical relations and explanations stipulated in the corresponding design code for each country are given in Table 16. The comparison of these periods with the ones obtained from structural analyses is shown in Table 16. The empirical formulas used in Table 16 are directly taken from the seismic design codes currently used by countries.


**Table 16.** Comparison of the natural fundamental periods for selected countries.

The fundamental periods obtained from the structural analyses for all countries were constant since the structural characteristics of the sample RC buildings models did not change. Empirically, the smallest period values were obtained for Albania, while the highest periods were obtained for Türkiye. The empirical periods suggested for Albania were lower than the periods obtained from the structural analysis. For the other five countries, the empirically suggested period values were higher than the period values obtained from the structural analyses.

### *4.2. Comparisons of Limit States*

In this study, the target displacement values for the different number of storeys were obtained from the structural analyses for each country, considering the limit states in Eurocode 8 for six different countries. The comparison of target displacements of sample RC models for Albania is given in Table 17.


**Table 17.** The obtained target displacements of sample RC models for Albania.

The target displacements suggested by the seismic design code for the first three earthquakes in Albania provide target displacements in which the acceleration values measured in earthquakes are taken into account. However, the target displacements predicted for the structure for the last two earthquakes and the target displacements obtained under the effect of the earthquake were exceeded. This suggests that the target displacements are adequately represented for some earthquakes, while it is not sufficient for others.

The comparison of target displacements of sample RC models for Bosnia and Herzegovina is given in Table 18.

**Table 18.** The obtained target displacements of sample RC models for Bosnia and Herzegovina.


The target displacements suggested by the seismic design code for the first three earthquakes in Bosnia and Herzegovina do not provide target displacements in which the acceleration values measured in earthquakes are taken into account. However, the target displacements predicted for the structure for the last two earthquakes and the target displacements obtained under the effect of the earthquake were not exceeded. This suggests that the target displacements are adequately represented for some earthquakes, while it is not sufficient for others.

The comparison of target displacements of sample RC models for Croatia is given in Table 19.


**Table 19.** The comparison of target displacements of sample RC models for Croatia.

The target displacements suggested by the seismic design code for all earthquakes in Croatia provide target displacements in which the acceleration values measured in earthquakes are taken into account. It shows that the seismic hazard is adequately taken into account in the structural analysis for all the selected earthquakes.

The comparison of target displacements of sample RC models for Serbia is given in Table 20.

The target displacements suggested by the seismic design code for all earthquakes in Serbia provide target displacements in which the acceleration values measured in earthquakes are taken into account. It shows that the seismic hazard is adequately taken into account in the structural analysis for all selected earthquakes.

The comparison of target displacements of sample RC models for Türkiye is given in Table 21. As seen in Table 21, the target displacements suggested by the seismic design code for the first, second, and fifth earthquakes for Türkiye provide target displacements in which the acceleration values measured in earthquakes are taken into account. However, the target displacements predicted for the other earthquakes for these structures were exceeded. This suggests that the target displacements are adequately represented for some earthquakes, while it is not sufficient for others.


**Table 20.** The obtained target displacements of sample RC models for Serbia.

**Table 21.** The obtained target displacements of sample RC models for Türkiye.


The comparison of target displacements of sample RC models for Iran is shown in Table 22.

The target displacements suggested by the seismic design code for the first two earthquakes for Iran provide target displacements in which the acceleration values measured in earthquakes are taken into account. However, the target displacements predicted for the structure for the last three earthquakes and the target displacements obtained under the effect of the earthquake were exceeded. This suggests that the target displacements are adequately represented for some earthquakes, while it is not sufficient for others.

In addition to the structural analysis according to the number of stories, the local soil class change was taken into account. The structural analyzes were carried out only for the four-storey RC building model since it is aimed to reveal the soil class effects. In the previous structural analyses, the ZD soil class envisaged in Eurocode-8 was taken into account. In this section, structural analyzes were made separately for each earthquake by choosing the ZA class in the same code. The recommended properties in the code for these two soil types are given in Table 23. The target displacements for selected earthquakes for each country for the ZA soil class type were given in Table 24.


**Table 22.** The obtained target displacements of sample RC models for Iran.

**Table 23.** The characteristics of local soil types considered in this study [147].


### **Table 24.** Comparison of target displacements for the ZA soil class type.


Another parameter chosen in order to put the effect of different structural conditions in common was the importance class of the structure. While the IV class was selected in the previous analysis, it was considered as the II class in the new analysis. The only difference in the initial analysis is the building importance class, all other features remained the same. Selected building importance class characteristics are given in Table 25. The target displacements for selected earthquakes for each country for the II class were given in Table 26.


**Table 25.** Selected importance classes for buildings [147].


**Table 26.** Comparison of target displacements for building important class II.

In addition to all these different structural conditions, the concrete class is also considered as a variable. While previous analyzes were performed for the C20 concrete class, new structural analyzes considered the C12 concrete class with lower properties for all load-bearing elements. The target displacements for selected earthquakes for each country for the C12 concrete class were given in Table 27.

72


**Table 27.** Comparison of target displacements for the C12 concrete class.

### *4.3. Evaluation of Existing Building Stocks*

### 4.3.1. Albania

According to the Albanian Institute of Statistics (INSTAT) 2001, the Albanian building stock primarily consists of four typologies, namely brick and stone, prefabricated, wood, and other building materials. However, when referring to the recent census of 2011 (IN-STAT), information on building materials is not included and houses are classified based on their heights and construction period. Table 28 presents a summary of the Albanian building stock based on existing information (INSTAT 2001) [148]. Accordingly, the 'RC and masonry' type represents the biggest part of the current building stock.

**Table 28.** Albanian building stock [147].


According to the Albanian Institute of Statistics (INSTAT) 2011, one-storey buildings account for 85% of the total building stock corresponding to the accommodation of the half population of the country. They were mostly built with unreinforced masonry and reinforced concrete frames with infill walls. However, the total number of multi-storey houses in Albania is significantly lower compared to one-storey houses, but they shelter the remaining half of the population. During the recent earthquake sequences in 2019, multistorey buildings were significantly affected, resulting in higher damage in the stricken areas. While the available data given in Table 24 is outdated, they highlight an important indicator (design code) on the construction year of the housings. An important portion of the current building stock was built before 1990 showing a lack of adequacy to the modern code requirements [17]. Therefore, it is likely that there were deficiencies affecting the seismic performance of buildings constructed in this time period.

### 4.3.2. Bosnia and Herzegovina

According to the available data for Bosnia and Herzegovina (CBS 2013) [149], it is noted that, from the total of 1,078,156 buildings, 60.72% are structures made of brick, stone, and concrete, 35.08% of reinforced concrete and steel frames and only 4.20% of wood and light material [73]. The majority of the structures are either confined masonry buildings or RC buildings constructed according to the regulations from 1981 (35%), considering age distribution from 1981–1990. Since 1991 Prestandards (ENV) have been applied and this accounts for 18.9% of all buildings being either RC buildings or confined masonry buildings. The application of Eurocode 8 started after 2006 accounting for 2.0% of all buildings (as well as RC buildings or confined masonry buildings). Masonry structures with rigid floors were mainly constructed in the period from 1971 to 1980, amounting to 33.6% of all structures built in Bosnia and Herzegovina. Brick masonry structures with rigid RC slabs were built in the period from 1946 to 1970, amounting to 6.6% of all the structures built in Bosnia and Herzegovina. The remaining 4% is devoted to stone masonry buildings with wooden floors constructed before 1945. Seismic vulnerability assessment of structures in Bosnia and Herzegovina is mainly done by individual researchers [150–153]. At the moment, Bosnia and Herzegovina does not have a well-organized and efficient database of structures and building's typologies. Several studies were conducted to determine the vulnerability of buildings in several cities of Bosnia and Herzegovina, like Banja Luka and Sarajevo [74]), Visoko [154], and Tuzla [155]. For the first time, the specific site and its influence on the vulnerability were taken into consideration in the Tuzla region [155]. Currently, 700 structures in the city of Sarajevo are being examined and a database is being created [156]. Based on all this preliminary analysis, it is clear that most of the existing building stock in Bosnia and Herzegovina does not possess sufficient resistance to ground motions that may be expected in this region. It is necessary to construct a detailed database taking into account all the data required to conduct adequate seismic assessments and perform a seismic risk assessment. Without this database and conducted calculations, it is not possible to construct an effective disaster management plan.

### 4.3.3. Croatia

According to the 2011 Census, the total number of dwellings in Croatia by year of construction was 1,496,558. Of that, 13.2% were built before 1945, which means that they did not follow any building codes. Building design and construction in Croatia did not follow earthquake-resistant building rules until 1948 [157].

Masonry houses used timber floor constructions until 1920. Most of these structures were constructed between 1860 and 1920 and are now part of Croatia's historic town centers, most of which are categorized as historical heritage. These structures were not intended to withstand significant horizontal ground motions (e.g., earthquakes). After 1930, the first semi-prefabricated RC floors were installed, followed by monolithic RC floors in 1964. After the Skopje earthquake in 1963, the first seismic building codes were developed and later modified. In addition, following the earthquake in Skopje in 1963, masonry structures throughout the former Yugoslavia were erected systematically using horizontal tie-beams and vertical tie-columns to achieve confined masonry. The load-bearing system in reinforced concrete structures (RC frames and RC shear walls) was built in accordance with

the seismic regulations enacted in 1964 (following the 1963 Skopje earthquake) and 1981 (following the 1979 Montenegro (coast) earthquake). Eurocodes were gradually adopted as voluntary structural design norms between 1992 and 1998. Due to the challenges associated with the harmonization of new standards with old national legislation at the time, they kept a pre-standards status (ENV label). The final version was introduced in 1998, with the European standard (EN label), but the ultimate implementation began in 2005 with the adoption of the technical standards for concrete buildings (NN 101/05). Eurocodes were ultimately made a requirement in official usage in 2011, however, pre-standards were still used until the end of 2012 [147].

Predominant structural systems for the buildings in one of the Croatian cities (Osijek) can be summarized as follows [147]: Unreinforced masonry buildings made of old bricks with flexible floors, unreinforced masonry structures with rigid floors, confined masonry structures, RC frame structures, RC shear walls, and RC dual structures. For RC structures, the level of earthquake resistance design should be taken into account.

On December 29, 2020, an earthquake of magnitude 6.4 MW hit Sisak-Moslavina county with an epicentre 3 km southwest of the Croatian city of Petrinja. In the preliminary report on the consequences of the earthquake, a detailed description of the damage to residential low-rise and multi-family residential buildings is presented [158]. The following are the primary sources of damage and failure in low-rise residential buildings: Excessive lateral displacements of flexible timber flooring caused out-of-plane damage or failure of exterior masonry walls at the upper/top levels of older URM structures (built before World War II). Recent masonry structures have rigid floors, but they also suffered damage owing to the lack of vertical reinforcement at the bottom floor level. Due to the extremely high seismic demand, the in-plane damage pattern took the form of diagonal tension cracks in the walls. The major tensile stresses in the walls created by the earthquake surpassed the masonry tensile strength, resulting in the formation of inclined cracks (diagonal tension cracks). In certain situations, the quality of masonry materials and construction appeared to be poor, which was also a source of damage. The primary sources of damage and failure in multi-family residential buildings can be summarized as follows: Excessive lateral displacements of flexible timber flooring caused out-of-plane damage or failure of exterior masonry walls at the upper/top levels of older URM structures (built before World War II). In general, the failure process in low-rise and mid-rise structures is relatively similar.

Many older URM buildings were not properly maintained, and as a result, their condition was poor before the earthquake [159]. The level of damage is thought to have been impacted by the degradation of building materials and components (such as wooden floors and roofing) as well as the use of weak mortar.

Due to extremely high seismic demand, masonry structures with rigid floors built in the 1960s developed in-plane shear cracking at the building's base. The major tensile stresses in the walls created by the earthquake surpassed the masonry tensile strength, resulting in the formation of inclined cracks (diagonal tension cracks). The earthquake caused no structural damage to RC structures; nevertheless, minor damage to non-structural components such as chimneys occurred in several buildings.

### 4.3.4. Serbia

According to the 2011 Serbian Census of population, household, and dwellings, 85% of all dwellings in Serbia were constructed after 1945, i.e., in the period when there were at least some seismic design codes. Before 2019, the seismic design codes created and implemented in the former Yugoslavia were used. The first seismic design code was published in 1948, but it lacked detailed detailing guidelines for RC and masonry construction. The disastrous earthquakes that struck Skopje in 1963 and Montenegro in 1979 served as turning points in the creation of Yugoslavian seismic design codes. Following the 1963 Skopje Earthquake, the first complete seismic design code was published in 1964. Two years after the 1979 Montenegro earthquake, a new, much more advanced code was published. The seismic design of new structures in Serbia must comply with Eurocode 8—Part 1 [147]

as of 2019 [160]. However, although most buildings were constructed after 1945, a recent moderate-size Mw = 5.5 2010 Kraljevo earthquake revealed the vulnerability of the Serbian building stock. It should be noted that reinforced-concrete structures accounted for only 10% of the building stock in the affected area. As expected, buildings with unreinforced brick masonry walls and flexible diaphragms sustained notable damages while properly constructed modern confined masonry buildings remained undamaged. However, numerous one- or two-storey masonry buildings with rigid RC floors and horizontal ring beams suffered severe damage and/or partial collapse due to the inadequate design and construction and/or low-quality building materials and many multi-storey masonry buildings were damaged due to poorly planned and executed renovations and extensions [161]. These findings call for increased efforts toward a more realistic estimation of the vulnerability of the existing building stock in Serbia if one would like to obtain a realistic estimate of the seismic risk.

### 4.3.5. Türkiye

Most of the existing building stock in Türkiye does not have sufficient resistance to earthquakes. This is clearly seen from the observed damage caused by the recent earthquakes in Türkiye. Earthquake regulations are renewed over time and put into effect, especially after the large-scale loss of life and property [162–164]. Insufficient structural features of the existing building stock play an active role in losses in earthquakes. For this reason, these uninspected buildings, which constitute the majority of the building stock, should be examined, some of them should be strengthened and others should be evaluated within an urban transformation project. The need for low-cost housing as a result of unplanned urbanization due to population growth and migration to big cities in Türkiye has caused both the shift from residential areas to areas with high earthquake hazards and the growth of building stock with weak earthquake safety. Knowing the characteristics of both new buildings and relatively old buildings with weak earthquake safety is of great importance in order to make accurate earthquake risk and loss calculations of settlements. To reduce the damage caused by earthquakes and for effective disaster management, the earthquake risks of existing structures should be calculated realistically. In this context, it is of great importance to know the properties of the building stock that affect the earthquake behavior well, to make the risk and loss calculations correctly. In this respect, examining the Turkish building stock in terms of time and space is of great importance in earthquake risk calculations.

### 4.3.6. Iran

After the 1990 Manjil mega-earthquake, one of the biggest and most fatal incidents in the seismic history of Iran that claimed the lives of more than 40,000 people, several investigations were initiated by many researchers on the analysis of the damages and vulnerability of the building stocks in the similar earthquake-stricken areas. The catastrophe caused a turning point in the analysis and design approaches of buildings and several modifications to the Iranian Code of Practice for Earthquake Resistant Design of Buildings, Standard 2800, and the definition of many research programs [165]. A study was conducted on three earthquakes in Iran, including the 2003 Bam earthquake, the 2005 Zarand earthquake, and the 2006 Silakhor earthquake by Mahdi and Mahdi [166]. The Bam earthquake has been the biggest earthquake with the highest rate of fatalities in the country after the 1990 Manjil earthquake, in which more than 53,000 buildings were destroyed while the remaining structures were severely damaged [167]. Damage analysis of buildings after the 2003 Bam earthquake by Mostafaei and Kabeyasawa [168] showed that building stock in this city at the time of the earthquake was comprised of adobe, masonry (reinforced and unreinforced), steel, and concrete buildings. As shown in this study, the major building system type has been unreinforced masonry (for around 68% of the buildings), and only 24% of the buildings in the city had been designed seismic-resistant, having a structural system as per the Iranian seismic design code of practice. This is while even the remaining steel or

reinforced concrete (RC) damaged buildings suffered from inappropriate structural design, low-quality construction practices, and insufficient implementation controls. Buildings that have been destroyed or heavily damaged in the other two earthquakes have been mostly adobe or unreinforced masonry buildings, while inadequate seismic-resistant structural systems or unsuitable construction practices were recognized as the main reason for damages. According to the 2016 national census conducted by the Statistical Centre of Iran (SCI) on the residential building stock and different building types, it is understood that the five main types of building systems, i.e., concrete, steel, masonry, adobe, and wooden, could be recognized in Iran. The census shows that masonry, steel, and concrete structures contain 39%, 30%, and 27% of the building stock, respectively. The remaining building types were either wooden or adobe, with 0.14% and 4%, respectively, while the remaining 0.26% had no recognizable system [169]. The study by Bastami et al. [169] which proposes new seismic vulnerability models for building stocks in Iran, shows a considerable change in newer versions of the Iranian Code of Practice for Earthquake Resistant Design of Buildings, Standard 2800, in terms of response factor for calculating base shear in the equivalent static method. These revisions as well as other stricter regulations and modifications for the design and construction of seismic-resistant buildings are in line with the above-mentioned started programs and initiatives for more protection of structures in Iran.

### **5. Results and Conclusions**

Both the seismic parameters and the expected target displacements from the structures have been obtained by considering five earthquakes that occurred in six different countries with different seismic risks within the scope of the study. The highest PGA value for all considered earthquakes was obtained in the 2003 Bam (Iran) earthquake and is 0.970 g. The lowest measured PGA was obtained as 0.01 g for the Serbian earthquakes. While the measured PGA's for Croatia and Serbia provided the recommended PGA's, the recommended PGA values for Türkiye, Bosnia and Herzegovina, Iran and Albania were exceeded. PGA values were compared, considering the standard design earthquake with a 10% exceedance of probability in 50 years (repetition period of 475 years). Therefore, it is possible that these values can be met with the consideration of earthquakes with a larger repetition period. Considering the largest earthquake data as the ground motion level in regions with high seismicity risk means that the seismicity risk can be adequately represented.

The selected earthquake range in Albania is between 5.4–6.9. Medium-sized earthquakes are mostly in the range of 0.1–0.2 g. However, the acceleration of the 5.4 magnitude earthquake that occurred in Tirana in 1988 was recorded as very high (0.4 g), exceeding the expected acceleration value (0.28–0.3 g). Two earthquakes, one moderate (5.7) and the other large (6.9) were selected in Bosnia and Herzegovina. The first selected earthquake exceeded the expected acceleration value (0.17 g) at nearby stations and took values in the range of 0.29–0.43 g. However, the 6.9 magnitude earthquake created an acceleration value (0.01–0.4 g) far below the expected acceleration value (0.18–0.26 g) at stations approximately 200 km away. In three different earthquakes selected in Croatia, a small (4.9) earthquake, however, close to the recording station (6.4 km) created an acceleration of 0.0 g. The acceleration value created by the 6.4 magnitude earthquake 60 km away from the station was 0.04 g. The 6.9 magnitude earthquake that occurred in Montenegro in 1979 had an acceleration of 0.08 g in Dubrovnik, 105 km away, and 0.04 g in Makarska, 208 km away. All of the recorded accelerations are considerably lower than the expected acceleration values. The earthquakes considered in Serbia are medium-sized, and the distances of the earthquakes to the acceleration stations are also high. Moreover, the places where the stations are located are rocky. For this reason, the acceleration values formed were quite low. The lowest of the five earthquakes selected that occurred in Türkiye is 6.3 and the highest is 7.4. It is quite interesting that three earthquakes greater than 7 produce very different accelerations from each other. The lowest acceleration was recorded in Van (Mw= 7.2) with 0.182 g and Düzce (Mw = 7.2) with 0.823 g. However, very high accelerations were observed in Erzincan (Mw = 6.8) earthquakes in 1992 and Bingöl (Mw = 6.3) earthquakes in 2003 (Bingöl 0.511 g

and Erzincan 0.485 g). One of the main factors in recording very high acceleration values is the proximity of the recording station to the earthquake focus and the other is ground conditions. It is seen that very high acceleration values were recorded in three different earthquakes in Iran. The 7.37 magnitude earthquake that occurred in Manjil in 1990 was recorded differently at different stations. Accordingly, the acceleration value of 0.13 g in Qazvin, 0.086 g in Rudsar, and 0.538 g at the other station in Rudsar show how different geological conditions affect the acceleration value. The acceleration of the 7.35 magnitude earthquake that occurred in Tabas in 1978 was recorded as 0.64 g, and the acceleration of the 6.6 magnitude earthquake that occurred in Bam in 2003 was recorded as an extraordinarily large 0.97 g. It is clear that the very loose soil structure of the city of Bam played the most important role in such magnification of the acceleration value.

The highest loss of life/damaged buildings ratio was found as 0.24 for 17.08.1999 Türkiye (˙Izmit) and the lowest value was determined as 0.0006 for 26.11.2019 Albania (Durrës). While the highest loss of life among all earthquakes was 17,480 in the 17.08.1999 Türkiye (˙Izmit) earthquake, the most building damage occurred in the Albania (Durrës) earthquake of 26.11.2019 with ~90000 buildings.

In order to reveal the effect of different structural conditions within the scope of this study, the number of storeys, local soil class, building importance class, and concrete class were chosen as variables. There is complete agreement between the target displacements obtained for all variables. The target displacements increased for three different limit conditions as the number of storeys in the building increased. In the case of weak local soil properties, the target displacements were obtained larger. The values obtained for ZA are lower than the values obtained for ZD. At the same time, target displacements were found to be larger in buildings that were required to be used after the earthquake. The displacements obtained for the building importance class IV are larger than those obtained for the II. class. As the strength of the concrete decreased, the target displacements expected from the structure increased. This once again reveals that buildings with weak earthquake vulnerability require larger displacements.

However, it was examined whether the seismic risks taken into account for different countries are adequately represented. In this context, since the seismicity elements of each country differ, the losses resulting from the earthquakes vary. Therefore, it is obvious that the realistic determination of the seismic risk will result in a more realistic result with the performance levels expected from the structures. In this respect, the building stock characteristics and local ground conditions also directly affect the losses. The vulnerability of the existing building stock increases the structural damage.

Earthquakes occur in fragile parts of the earth's crust due to their formation mechanism. Loose layers near the surface cannot be a source of earthquakes in this sense. However, since such areas are areas of weakness, they allow the incoming tremor to reach the surface easily and stand out because they are geologically highly impacted areas. In this study, it is observed that the earthquakes selected in countries other than Bosnia and Herzegovina and Croatia occur under the influence of geological conditions. Selected earthquakes in Albania are mostly in Durres, Shkoder, and Tirana. The depression areas formed with the neotectonic uplift that started in the Pliocene period in Albania led to the formation of Quaternary lakes and plains. In these grabens, the thickness of which reaches 200 m, unstable soil formations at the swamp level cause earthquakes to be more effective [170]. In Serbia, mainly earthquakes occurred in Kraljevo. This area is in the current alluvial and Tertiary flysch structure. The second important earthquake zone is the Pec zone, which is also the flysch zone. Therefore, it can be said that earthquakes occurring in these regions are based on weak geological conditions. Almost all the earthquakes selected in Türkiye have occurred in the current alluvial areas (Erzincan, Kocaeli, Düzce, Bingöl, Van). Plain regime areas created by very thick alluvial structures and active tectonism continue to be sources of earthquakes. The Bam and Manjil earthquakes, which were selected from the earthquakes that occurred in Iran, were effective in the current alluvial basin-type areas. The reason for the occurrence of earthquakes in these areas can be considered as specific geological conditions.

Buildings constructed in loose and unstable ground conditions are the most vulnerable to earthquakes. For this purpose, it is necessary to choose the soil-building interaction correctly. Almost all the earthquakes selected in this article, which are considered important in the country where they occurred due to the damage caused, have resulted in severe damage due to incompatibility. One of the main purposes of this study is to show that the damages caused by earthquakes without borders are based on similar faults.

It is important to construct buildings in accordance with earthquake-resistant building design guidelines in earthquake-prone regions against the possibility of the recurrence of earthquakes that cause significant damage. This depends on the correct application of earthquake-resistant building design principles during the design and construction stages. The application of earthquake-resistant building design principles together with adequate supervision can be seen as the first step in minimizing the problems, both during the project and construction phases. In addition, the existing building stock should be determined quickly and reliably, and then strengthening and demolition procedures should be decided in buildings that do not have sufficient earthquake performance. At this point, the number of weak buildings under the effect of earthquakes should be minimized by utilizing urban transformation.

**Author Contributions:** Conceptualization, E.I., M.H.-N., H.B., N.A., A.B., E.H., B.B., H.B.Ö. and S.E.A.H.; methodology, E.H., S.E.A.H., E.I., A.B. and E.H.; software, E.I., N.A., H.B. and M.H.-N.; validation, E.H., A.B., H.B.Ö. and S.E.A.H.; formal analysis, B.B.; investigation, E.I., M.H.-N., H.B., N.A., A.B., E.H., B.B., H.B.Ö. and S.E.A.H.; resources, E.I., M.H.-N., H.B., N.A., A.B., E.H., B.B., H.B.Ö. and S.E.A.H.; data curation, E.I., M.H.-N., H.B., N.A., A.B., E.H., B.B., H.B.Ö. and S.E.A.H.; writing—original draft preparation, N.A., A.B., E.I., B.B. and M.H.-N.; writing—review and editing, S.E.A.H., N.A., M.H.-N., E.I. and E.H.; visualization, H.B.; supervision, E.I., N.A., M.H.-N. and B.B.; project administration, E.I.; funding acquisition, M.H.-N. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Data sharing is not applicable.

**Conflicts of Interest:** The authors declare no conflict of interest.

### **References**

