EARTHQUAKE VULNERABILITY ASSESSMENT FOR HOSPITAL BUILDINGS USING A GIS-BASED GROUP MULTI CRITERIA DECISION MAKING APPROACH: A CASE
STUDY OF TEHRAN, IRAN
M. R. Delavar
a
, M. Moradi
b
, B. Moshiri
c a
Center of Excellence in Geomatic Engineering in Disaster Management, School of Surveying and Geospatial Engineering, College of Engineering, University of Tehran, Iran
– mdelavarut.ac.ir
b
School of Surveying and Geospatial Engineering, College of Engineering, University of Tehran, Iran – milad.moradiut.ac.ir
c
Control and Intelligent Processing, Centre of Excellence, School of ECE, University of Tehran, Tehran, Iran – moshiriut.a.cir
KEY WORDS: Group Multi Criteria Decision Making, GIS, Disaster Management, Earthquake Vulnerability Assessment ABSTRACT:
Nowadays, urban areas are threatened by a number of natural hazards such as flood, landslide and earthquake. They can cause huge damages to buildings and human beings which necessitates disaster mitigation and preparation. One of the most important steps in
disaster management is to understand all impacts and effects of disaster on urban facilities. Given that hospitals take care of vulnerable people reaction of hospital buildings against earthquake is vital. In this research, the vulnerability of hospital buildings
against earthquake is analysed. The vulnerability of buildings is related to a number of criteria including age of building, number of floors, the quality of materials and intensity of the earthquake. Therefore, the problem of seismic vulnerability assessment is a multi-
criteria assessment problem and multi criteria decision making methods can be used to address the problem. In this paper a group
multi criteria decision making model is applied because using only one expert’s judgments can cause biased vulnerability maps. Sugeno integral which is able to take into account the interaction among criteria is employed to assess the vulnerability degree of
buildings. Fuzzy capacities which are similar to layer weights in weighted linear averaging operator are calculated using particle swarm optimization. Then, calculated fuzzy capacities are included into the model to compute a vulnerability degree for each
hospital.
Corresponding author
1. INTRODUCTION
Tehran is situated in a seismically active region in Middle East and it is dramatically threatened by earthquake M Moradi,
Delavar, Moshiri, Khamespanah, 2014. In recent years, Tehran became a centre for many financial, educational and
recreational activities. Rapid urban growth lack of urban planning and urban sprawl render the city extremely vulnerable
to earthquake. Among all facilities in Tehran metropolitan area, hospitals have a remarkable value because they are related to a
vulnerable category of people. A number of researches have been undertaken in order to assess the vulnerability of habitats
and to estimate the number of deaths and casualties in the future earthquake Mansouri, Kiani, Amini-Hosseini, 2014;
SHAYANNEJAD ABEDINI ANGERABI, 2014; Sinha, Priyanka, Joshi, 2014. Considering the fact that many factors
are affecting seismic vulnerability of hospital buildings, this problem is a multi-criteria problem Rashed Weeks, 2003.
This paper applies a multi-criteria method in order to assess the vulnerability of hospital buildings against earthquake. In
addition, given that multi-criteria algorithms are ill-structured Chakraborty Joshi, 2014 which means that different multi-
criteria models may produce different results, in this paper a model based on Sugeno integral is applied to analyse the
vulnerability of hospital buildings. Moreover, more than one
expert’s judgments are included into the model to reduce the uncertainty of single expert systems. Firstly, a vulnerability
degree is calculated based on every expert’s judgments. Following that, a group multi criteria decision making model is
used to aggregate different experts’ vulnerability degrees and produce one overall answer. Sugeno integral which is able to
aggregate attribute values with respect to the interaction among them is employed in this research. In fact, Sugeno integral is
employed to serve two purposes in the current research. First of all, to aggregate attribute values and produce a vulnerability
map based on each expert’s point of view and for group decision making. In this paper 5 experts are asked to evaluate
the vulnerability of hospital buildings. Then, PSO is used to extract the optimum value of fuzzy capacities which are the
unknowns of the Sugeno model. Finally, these fuzzy capacities which are obtained through training process are used for
computing a vulnerability degree for each hospital building. 1.1
Related works
Seismic vulnerability assessment is a core process in disaster management and frequent efforts have been undertaken to
address this problem. A number of these researches were related to physical vulnerability which indicates the vulnerability of
buildings and structures against earthquake Milad Moradi, Delavar, Moshiri, 2015. Milad Moradi et al. 2015
proposed a GIS-based model using ordered weighted averaging operator that is able to analyse different seismic vulnerability
maps based on optimistic and pessimistic scenarios. A group multi criteria decision making model was proposed by Peng
2012 for seismic vulnerability assessment. They assessed seismic vulnerability using a number of different MCDM
methods in order to compare the results. A number of
This contribution has been peer-reviewed. doi:10.5194isprsarchives-XL-1-W5-153-2015
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researches addressed the problem of social vulnerability which indicates the degree to which human of a specific urban area are
vulnerable against earthquake. Ge et al. 2013 analysed social vulnerability of urban areas against natural disasters with a
multi criteria approach. Rashed and Weeks 2003 proposed an integrated multi criteria decision making model which is able to
evaluate both social and physical vulnerabilities. They employed a fuzzy model to manage fuzzy uncertainties
associated with input data. Earthquake vulnerability of urban facilities is assessed in some other researches. Considering the
fact that children are a vulnerable part of any society, Panahi, Rezaie, and Meshkani 2014 designed and developed a seismic
vulnerability assessment model for schools based on fuzzy analytical hierarchy process. They evaluated the impact of peak
ground acceleration on schools buildings in Tehran. Rezaie and Panahi 2015 developed a model for including geotechnical
parameters in a seismic vulnerability model based on multi criteria
analysis. Although
previous researches
have investigated a wide range of aspects of this problem,
vulnerability of hospital buildings have not been assessed before.
2. METHODOLOGY
