Evaluation of Seismic Reliability of Kermanshah Concrete Type Schools Based on Seismic Intensity Parameter

Earthquake is one of the most important natural phenomena that causes economic damages and human losses due to the damage and breakage of structures. The unfortunate economic and social consequences caused by earthquakes, determine the importance of evaluating and improving existing buildings against earthquakes. This issue is particularly important for schools and educational buildings. School buildings, due to their demographic structure, are important buildings whose safe design, implementation and control of behavior and performance are of great importance. Experience of past earthquakes shows that damage to schools can lead to high casualties and human catastrophe; therefore, design regulations also provide stricter rules and regulations for the design of educational buildings. Seismic performance control of existing educational buildings is also of special importance and various methods including linear and nonlinear analysis have been recommended by different regulations and instructions. On the other hand, there are many uncertainties in the study of structural performance that prevent a definite achievement of the structural performance response. Some of these uncertainties are inherent, such as the impossibility of predicting the intensity of future earthquakes, and some are due to errors in analysis and calculations, so the probabilistic expression of structural performance is a logical way to study structural performance. There are several methods to check the reliability of the structure that are different in terms of hypotheses, methods and accuracy, so the effect of uncertainty in each method should be considered appropriately. A review of past research shows that many studies have been conducted on the possible evaluation of the seismic behavior of concrete structures, but there are few studies on the behavior of real examples of such buildings. In this study, two repetitive types of Kermanshah concrete structural schools are non-linearly modeled and analyzed and evaluated using time-history dynamic analysis under the effect of 12 possible earthquake records, appropriate to the type of land and distance from the fault. In order to evaluate the seismic reliability of these schools, based on the specific levels of intensity, the probability of reaching the response to the corresponding values ​​is determined at different levels of damage. The maximum structural drift is considered as the response, and the performance levels defined in the FEMA356 guideline are considered as the failure criterion. The fragility curves of the studied schools have been compared and verified with the behavior of a sample of these schools in a real earthquake, as well as the fragility curves presented in the technical manual of the Hazus earthquake model. In this study, the non-linear behavior of important structures such as schools, which are designed in a linear way, is evaluated and compared. Also, expressing the probability of vulnerability of such structures for possible earthquakes can provide the performance of important structures in each region. The results show that the probabilistic expression of the structure's performance is a suitable method to express the behavior and performance of the structure. The type of ground of the school building and the distance of the building from the fault has a significant effect on the seismic performance and response of the structure. With the increase of storeys, the probability of reaching the school drift to different functional levels is always higher and by increasing the earthquake intensity this proability increases as well. Also, the structures of the studied schools, despite the irregularity in the plan, have a good performance in order to take into account the effects of earthquake intensity, site ground and site distance from the fault. This information can be widely used in crisis management, urban management decisions and future planning of the region.