فصلنامه پدافند غیرعامل
سال چهاردهم شماره 2 (پیاپی 54، تابستان 1402)

Passive defense is an issue that has received more attention in recent years. The concept of passive defense is that sometimes human societies face natural and unnatural problems. If there are appropriate plans for these events, the problems that arise in the communities as a result of these events are much fewer. There is no doubt that due to the existence of some centers in the cities, some places are of high importance. And it has been tried that these points are self-sufficient under any conditions, and as a result, these points can be protected against electric power outages. In this article, we divide the national electricity network into 8 micro-grids. Each of these micro-grids is allocated scattered production sources including active and reactive power, and then in such a way that these 8 micro-grids can be, continuously, and also act as an island, so that if something happens to any of these networks during incidents and they are disconnected from the main network for any reason, these networks can work as an island and respond to the needs of the loads of each part. In the following, the location and size of scattered production sources and capacitor banks are discussed using the whale optimization algorithm. By using this method, the network needs can be answered locally, and for this reason, high power losses and voltage drop can be avoided. To investigate the role of optimization in the first scenario, the number of units of distributed generation resources is 47 units and the maximum number of capacitor banks is 38 units. As a result of the optimal placement of these power generation units in the right places, the losses, which were equal to 227 kW before the optimization, have significantly decreased after the optimization and have decreased to 122 kW.

The purpose of this article is to investigate the resilience of Mehrabad airport in possible crises such as war and earthquake through the simulation of emergency population evacuation. The research method is descriptive-analytical, in terms of solving the combined problem and the type of explanatory results. . Collecting field and documentary information has been done. The statistical population includes 160 specialists, academic staff and graduate students. Random sampling and Cochran's formula were used. After conducting the interview and completing the questionnaire, compatible scenarios are obtained from Wizard software and then modeling in normal, disaster and optimistic mode with maximum two incompatible factors is considered in Any Logic. The results of the simulation have shown that the fourth scenario is in a more critical condition than the other scenarios with an evacuation time of 125 minutes and a simulation time of 87.19. In scenario 1, normal conditions, since all entry and exit doors are healthy, the percentage of evacuation of people is maximum immediately after the beginning of the crisis, the presence of obstacles has no effect on the creation of a population node, and over time, the population gradually leaves. In the case of a disaster, time Draining is 100 and simulating 59.11 minutes. The resilience of airport hall number 2 is suitable under normal conditions, but in the event of a crisis and an increase in density, fear and speed, it is very low. Unlike the previous studies that have a one-dimensional view of the emergency evacuation issue, this article has a mixed approach.

Dams are one of the vital components of human societies and one of the strategically important assets of any society with a significant role in the sustainable development of the country. In this research, the damage caused by the blast of a double curvature arch concrete dam has been evaluated according to the mean velocity and frequency caused by the blast in the near-field. The model of the material used is the numerical simulation include the explosives, air, water, and concrete, which has been modeled. The problem-solving method used to apply the blast in modeling is Load Blast Enhanced. Using this method, the propagation of the pressure wave caused by the blast and finding the critical points of the dam body against the blast have been investigated. Then, the structural responses and the dam damage characteristics in different blast scenarios have been investigated according to the change in the blast depth, the distance from the concrete dam body, and the blast load. Also, by using vibration parameters such as peak velocity summation (PVS) and mean frequency (MF), the combined spectrum has been evaluated and proposed as a way to design a blast-resistant dam and find a safe standoff distance in case of emergency. Finally, two PVS-MF spectra have been suggested according to the charge weight and their distance for optimal and useful classification of dam damage according to three modes: slight, moderate, and severe, for initial and critical evaluation.

Today, tunnels are one of the main vital arteries for a city, which are developing significantly. The development of today's societies has caused the need for tunnels in various sectors, including urban public transportation, intercity transportation, and water and sewage collection and transmission networks, etc. It goes without saying that for underground structures such as tunnels, the existence of faults and consequently earthquakes are serious threats among natural hazards. Although tunnels should not be located near active faults, sometimes passing through them is unavoidable. Sometimes, after the construction of the tunnel, the existence of the fault is known. In such cases, the deformation caused by the fault is considered a big concern and has a significant effect on the behavior of the tunnels. Meanwhile, due to the fact that most urban shallow tunnels are built in loose ground, the necessity of studying the behavior of tunnels and ensuring the safety of these structures against failure is of great importance. The advantage of numerical methods, in this research, the effect of different parameters such as the thickness of the piece, the depth of the tunnel placement and the fault angle on the behavior of piece tunnels has been investigated using FLAC 3D software. The main goal of the research was to know the possible failure mechanism of segmental tunnels due to faulting. In this research, 24 numerical models were built to understand the behavior of segmental tunnels under the effect of reverse faulting. The validation of this numerical modeling is with the physical model of Kiani et al. The ways to improve the performance of segmental tunnels when faced with reverse fault movement is to increase the rigidity of the tunnel. In this research, the effect of the depth of the tunnel placement due to the reverse fault was also investigated. It was observed that increasing the depth of the tunnel placement when facing reverse faulting leads to a decrease in the deformation of the tunnel diameter. Also, the effect of changing the fault angle for the tunnel was investigated. Increasing the angle of the fault causes the change of places created on the ground surface and the displacement of the tunnel roof to decrease.

Due to the emergence of terrorist threats in recent years, in the form of air attacks, sudden explosions of ammunition and suicide bombers around special and strategically important structures such as arched concrete dams that have a very high capacity for storing surface water, the performance and design of this The threatened structures are mandatory and their possible failure can cause a huge flood, which can cause huge financial and human losses downstream. Therefore, the purpose of this research is to identify the nature of the explosion along with investigating the vulnerability of concrete dams. arching and investigating the parameters affecting the non-linear response of the structure by comparing the location change of the dam crest and the amount of compressive and tensile damage for dam-piling and dam-piling-reservoir systems due to explosion. The results of the sensitivity analysis for the linear and non-linear behavior of concrete showed that it is necessary to model the non-linear behavior of concrete in order to investigate the behavior of arched concrete dams against dynamic loads, especially loads of an impact nature such as explosion. In the linear mode, the changes in the amount of the explosive material in the time history of the location change are not noticeable and the permanent location change of the crown is very close to each other for all the explosive loading conditions and finally returns to the final value of the static condition. Also, comparing the outputs of linear and non-linear analysis showed that the difference between the answers from the explosion of 500 kg of TNT at a distance of 8 meters to 1500 kg of TNT at a distance of 2 meters has an increasing trend, so that the difference between the response of the change of location The background values for the linear and non-linear states are 18.7% and 25.2%, respectively, which emphasized the necessity of considering the non-linear behavior of concrete, especially for explosion in the near field. By comparing the maximum displacement responses of the full tank state, it was concluded that the presence of the tank reduces the influence of the reference point position and the amount of explosive charge on the crown response, compared to the empty tank state. Also, the results showed that in the full tank state The extent of pressure vulnerability is greater for the downstream, which indicates the application of hydrodynamic pressure of reservoir water to the downstream elements of the dam, and this happened due to the shape of the arch, but in the case of an empty reservoir, due to the absence of hydrodynamic pressure, the extent of this The damage was less.

One of the most important issues that is always in the attention of organizations responsible for crisis management is choosing a suitable place for the temporary accommodation of populations affected by disasters. Due to the fact that Iran is located on one of the two earthquake-prone belts in the world and the existence of many faults, the occurrence of earthquakes in the plateau of Iran is a natural thing. So that the earthquake of 1357 caused the damage and destruction of Tabas city and most of its neighboring villages. Therefore, the purpose of this research is to evaluate the spatial-spatial indicators for creating multi-purpose bases and to specify suitable areas in Tabas city. The required data were collected in the framework of the descriptive-analytical research method from the library method and by referring to the relevant sources and organizations. In this regard, 16 indicators were measured based on efficiency, compatibility and safety criteria using the Analytical Hierarchy Process (AHP) and then the most appropriate locations were identified through weighted overlapping layers and applying these coefficients in the GIS software environment. The results showed that 0.78% of the city's area is in very good condition, 43.59% is in good condition, 48.06% is in bad condition and 7.57% of land is in very bad condition to create a crisis management base.

One of the most important challenges at the time of war is the timely treatment of the war wounded and avoiding the reduction of combat power, which is usually solved by building field hospitals. The armed forces of the Islamic Republic of Iran gained valuable experience in the construction of field hospitals during the sacred defense period. The location and construction of these buildings along with the innovation, initiative and scientific creations of the fighters of Islam has developed.From the establishment of a tent or the construction of a roofed frame for relief in the beginning of the war, it turned into the construction of explosion-proof field hospitals with concrete structures camouflaged deep in the ground. So that by doing these creations, the index of "average time to send the wounded to medical centers" which was 14 days in the First World War, three days in the Second World War and 12 hours in the Vietnam War; After the construction of well-equipped and safe hospitals in the closest distance from the front line, it was reduced to three hours. This indicator was reduced to one hour with the construction of Imam Sajjad (a.s.) field hospital in Faw front (Valfajre 8) and to less than half an hour at the end of the war with the construction of numerous centers. Of course, due to reasons such as time constraints, along with the severe lack of specialized tools and equipment for the construction of field hospitals, some of the principles of passive defense are ignored in the selection and construction of these valuable structures. Because it is important to examine the strengths and weaknesses of these hospitals and especially the types of their structures, taking into account aspects of passive defense to build better field medical centers in the future; Therefore, the current research has identified and prioritized the effective dimensions, factors and indexes in the construction of field hospitals, taking into account the aspects of passive defense. For this purpose, the method of structural equations was used with SPSS software and Friedman's non-parametric test. The ranking results of field hospitals evaluation criteria, taking into account passive defense criteria, indicate that the criterion "the need to pay attention to the issue of location" in the security risk subgroup, as well as the criterion "the need to pay attention to the ability to change the location of field hospital structures" in the construction risk subgroup and structural infrastructure have the highest priority with an average rating of 20.12 and 18.79, respectively. At the end, suggestions were made for building more qualitative field medical centers by considering aspects of passive defense in future battle scenes.

The complete ineffectiveness of weapons against enemy attacks led to the creation of a passive defense approach. On the other hand, the close relationship between the environment and users caused the rapid deterioration of the passive defense approach to environmental issues even though many studies in this field have dealt with the principles of architectural design, buildings with a high importance factor. To the extent that there is a lack of attention to landscape design in the national building regulations, the area design has been neglected in a brief section. In this case, landscape architecture can be practical support in passive defense, reduce injuries, and support users when accidents occur. This article assumes that landscape architecture can be the savior of architecture and urban planning with a passive defense approach. In other words, using the principles of passive defense in landscape design is one of the measures that can be used at different levels, from planning to design, to reduce the severity and extent of risks caused by natural and unnatural risks. Nevertheless, most of the studies in this field are dedicated to architecture and urban planning, and practical solutions in applying the passive defense approach have been neglected. Based on this, the current research is of applied type, with a qualitative approach, and based on the case study and logical reasoning research method to answer the question: "How landscape as architecture can save the built environment?" has been written. The results demonstrated that the principles of defensive landscape design could be explained in two macro dimensions (spatial scale, uses, diversity of spatial qualities, placement, and positioning) and micro dimensions (artificial elements-furniture, material, natural landscape elements).

What in this research it has been addressd vulnerability  review and assessment transportion networks  and its interaction analysis Emphasis on urban air ports against man made threats and proposals to reduce vulnerability based on the principles and foundations of passive defense is. Airports by providing  fast shipping platform and passenger and with high capacity between regions with a long distance to the comprehensive development of countries and even the provinces help a lot so that it as one of the symbols of development Civilian airports are currently considered as one of the vital and valuable assets in any country that is considered as one of the air borders, and will be very important, so that taking measures to reduce their vulnerability to threats is necessary and unavoidable, so that The slightest disturbance in its functioning or damage to its body causes huge material and moral damages. The current research is an applied research, and it is in the category of descriptive-analytical research, the required information has been collected using documentary methods, including library documents, observations and field. For this purpose, a number of 32 experts were chosen as experts and FEMA method was used for risk analysis and the information was analyzed using Expert choice software and AHP technique. The findings of the research show that the assets of city airports in different sectors are seriously vulnerable to military attacks and man-made terrorist acts Of course, according to the type, nature and function of each of the infrastructure elements, the degree and level of vulnerability is different And it is possible to explain the factors of increasing vulnerability and the ways to reduce it for each key asset, with the aim of ensuring the continuity of activity and maintaining the airport infrastructure and protecting human lives.