J. Basic. Appl. Sci. Res., 3(8)675-681, 2013 © 2013, TextRoad Publication ISSN 2090-4304 Journal of Basic and Applied Scientific Research www.textroad.com * Corresponding Author: Nima Gheitarani, Young Researchers Club and Elites; Hamedan Branch, Islamic Azad University, Hamedan, Iran. E-mail:n.gheitarani@yahoo.com., Tel:+989356801636 Explaining the Effective Measures in Decreasing the Vulnerability of Urban Area against Earthquake Using AHP Model (Case study: Tehran, a Metropolis) Nima Gheitarani 1* , Razieh Ghadarjani 2 , Meghdad Kahvand 3 , Seyyed Ali Mortazavi Mehrabadi 4 1, 3 Young Researchers Club and Elites; Hamedan Branch, Islamic Azad University, Hamedan, Iran 2 Department of Art and Architecture, Hamedan Branch, Islamic Azad University, Hamedan, Iran 4 Department of Architecture, Beiza Branch, Islamic Azad University, Beiza, Iran ABSTRACT Earthquake is one of the natural disasters. If it happens, it creates in compensable troubles and losses in the human environment. Tehran, as a metropolis, is always apt to earthquake due to lying on the belt of Alps- Himalaya which is prone to earthquake and the existence of fault in its north and south area. The specialists and authorities in the field have always presented ideas and measures to reduce the probable losses. In the he present article, attempt has been made to recognize the measures and analyze to see to what extent they are practical. The idea and impractical measures do not meet the needs of Tehran with the undeniable characteristics such as being populated, having compacted dwelling texture, lacking per head and standard observance. The research methods used are descriptive–analytical and statistical. AHP model and expert choice 2000 software have been used to evaluate the measures. The result showed that material resistance and the width of lattice work, among the reducing measures of vulnerability, are the most important ones respectively. The regions 8, 22, and 1 have possessed a better status respectively regarding the investigated measures related to the extent of vulnerability. KEYWORDS: earthquake, AHP model, Tehran as a metropolis, vulnerability. 1. INTRODUCTION Earthquakes have caused the most devastating natural disasters in the 20 th and 21th centuries (Bryant, 1993; Marcuson et al, 2003). Unlike many other types of disasters, originating primarily from natural forces, there is no warning. For many victims the experience of an earthquake is one that causes inexpressible, sudden and seep shock, often with long–term ongoing psychological consequences, and the impact is often widespread (for instance, see: Akason, 2004; Bo dvarsdo ttir and Elklit, 2004; Cannon, 2003; Basog lu et al, 2002; Durkin, 1993). The vast area of Iran, because of its special geographical status (fault and climate condition), has always faced various natural disasters, particularly earthquake which has caused a lot of financial and mortal damages. Moreover, the correct technique against earthquake not being applied by human, as a factor of disaster, has doubled the damages. Tehran with the area of some 700 kilometers is one of the biggest cities of the world which owns particular characteristics. The faults surrounding its north and south regions and the buildings built on the faults necessitate more attention to be paid to recognize dangerous points and provide measures to reduce the probable dangers. To fight with the damages which occur during and after earthquake, the specialists in the field have designed some measures. Of these measures we may refer to lattice work or grid, the number of storeys of the building, the use of the lands etc. So, the main purpose of the article is the recognition of the measures for evaluating the degree of urban vulnerability against earthquake. The sample for this case study is the northern regions of Tehran, for these areas are closer to the brake and potentially are apt to receiving the danger of earthquake. 2. The background of earthquake in Iran Due to resting on the Alps–Himalayan belt, Iran is one of the five countries which are prone to earthquake (Golabchi & Taiebat, 2011). During the last century, Iran has experienced 130 earthquakes as large as more than 7.5 Richter (Ghafari – Ashtiani, 1992). 17.5 percent of the devastating earthquakes of the world happen in Iran (Baiat, 2003). As the map of the width of earthquake shows the two–third of the country's area rests on the axis of dangerous earthquake (Asgharimoghadam, 1999). In the regions located between Alborz and Zagros mountains, the alternate occurrence of earthquake is less. Thus, strong and devastating earthquakes are expected there. (Memari & khandani, 1993). Based on the officially known statistics in the last 25 years, six percent of the mortality of the country has been due to earthquake (Zangiabadi & Tabrizi, 2005). Studies concerning the statistics of earthquakes larger than 6.5 Richter imply that some forty earthquakes have happened in Iran during the last century. Therefore, it should be noted that an intense earthquake happens every 2.5 years, as an average, in our country (Arian, 2003). Tehran has been built in south skirt of central Alborz Mountains and on the deposition of quarter, and its south is located on north – west of the vast desert of central Iran. The sudden and 675