|
|
:
|
As the natural phenomena during earth planet life, natural disasters have always existed and also will exist, and in most cases, they irrecoverable damages on human being settlements and cities. Among these, as one of the most important natural disasters, earthquake, during a short period of time has always caused irreparable damage to the body of human being settlements. Nowadays, in spite of the technological advances and increment of human being knowledge and abilities to control natural disasters, cities are still at earthquakes risk and are vulnerable from this perspective. Despite of impossibility in preventing an earthquake, thinking of the strategies can minimize the damage caused. One strategy to manage crisis is to deal with the damage caused by natural disasters in urban settlements, is to pay close attention to vital arteries. Meanwhile, the role of the network of passages as the oldest vital artery is indisputable. Among this, the role passages network as the time-worn vital artery is Irresistible. The citiy communication network has a fundamental role toward earthquake vulnerability, so after an earthquake, if it has not damage and maintains its efficiency, the earthquake casualties will decrease, so it make the dangerous situations escape possible, access to safe areas, and even easy possibility vehicles traffic. Iran is located in Himalayan- Alpine orogenic belt center and it is a prone area for earthquake. The recent decades devastating and catastrophic earthquakes have shown there is no a part to be safe from earthquake hazards. Since, sanandaj is located on relatively quiet structural zone of sanandaj- sirjan and it is not the earthquakes hotspot, low width of sanandaj- sirjan zone and passing way of two famous faults of young Zagros and Marivan- Sirjan, Sanandag is threatened to surrounding earthquakes. Crisis managers declare one reason for the expanding dimensions the earthquakes are the lack of timely relief resulted from the road and urban communications networks. So, assessing the urban passage network vulnerability road network during earthquake hazard and planning to reduce these damages is very vital. Therefore, this research, three models of Network Analysis, WLC and Maximum Likelihood classification were used to assess the of communication networks vulnerability in Sanandaj during earthquakes and the criteria for area of housing, building materials, some kind of ownership, building type and distance from sensitive and service centers were selected. Each criterion has sub-criteria they were weighted with AHP model. Finally, they were overlapped with WLC and Maximum Likelihood classification models and a vulnerability output map obtained for each model. Noted, the Network Analysis model has no output map and it was identified by analyzing the standardized the vulnerable areas layers and the vulnerability factors on each region. The results showed during earthquake, the zone one and two had the highest passage vulnerability with very inappropriate and inappropriate degrees and zone three has the least passage vulnerability with an inadequate degree. Factors including high population density, high households’ density and floors, low area and being small of buildings, low quality and durability of materials used in buildings had a major role in these areas high vulnerability of. Meanwhile, the high degree of vulnerability in informal and time worn textures is than than new ones.it is worth nothing there is slight difference between the WLC results and Maximum Likelihood classification models, due to the WLC model risk aversion and the Maximum Likelihood classification model riskiness.
|