Journal of Geography  & Natural Disasters
Acesso livre

Abstrato

Earthquake Vulnerability Mapping Using Binary Comparison Matrix and Analytical Hierarchical Process (AHP) In Lalmatia, Dhaka

Tanzila Aktar Shawon1, Mohammad Mizanur Rahman1*, Akter Mahmud1, Mohammad Zibon Ahmmed2, Sabrina Sharmin3

Background: Bangladesh is in a high-risk zone of earthquake hazard due to historical records, geological evident and recent trends in earthquake. The Comprehensive Disaster Management Program (CDMP) predicting a seven-magnitude earthquake causing serious human tragedy in Dhaka owing to the defective structure. This study considered the characteristics of RCC building elements and their behaviors to assess the risk against earthquake vulnerability in Lalmatia of Dhaka city. The purpose of this study is to assess the earthquake vulnerability in the existing buildings using Turkish method and to investigate the earthquake vulnerability priority using Analytical Hierarchy Process.

Methods: This study considered the Turkish method for calculating building seismic performance by Peak Ground Velocity (PGV). In the method of this research, a pair wise comparison matrix for a numerical relationship between two elements and the Analytical Hierarchical Process (AHP) model has been applied to decide in weight and to get rank of the vulnerability factors. By weighted sum vector among the six factors and calculating Vulnerability Index (VI), the overall vulnerability were identified in Lalmatia. Using Geographic Information System (GIS) and defining an ordinal scale of calculated result, the vulnerability status of single buildings of the study area is presented here.

Results: This research demonstrates that 8.23% buildings are highly vulnerable and 14.24% buildings are moderately vulnerable to earthquake. About 77.53% buildings are less vulnerable. As the study area is in a major urban center (Dhaka City), the scenario of unplanned urbanization increases the overall vulnerability to higher scale. With the value of Turkish method the vulnerability level is higher compared to AHP method. At the time of AHP model the range of vulnerability levels is depended on huge population, very high construction age, narrow road and building use as residential.

Conclusions: This research examines the earthquake vulnerability in the areas of Lalmatia and Dhaka, with a focus on the use of GIS mapping to provide detailed information on the buildings vulnerability. The model that is applied in this study will expressly contribute to the vulnerability appraisement and also helps to take mitigation attempts of Dhaka city against earthquake.