Assessing the discrete and systemic response of the Built Environment to an earthquake

Abstract

• Discrete and Systemic Built Environment Vulnerability Index. • Systemic dependencies between the elements of Vulnerability. • Analysis at Mid-scale level of Urban area. • Identification of possible isolated street networks. • Rapid Visual Screening of Buildings. The built environment is an outcome of the land development process that expresses the community's relation to its surroundings. In the context of earthquakes, the built environment directly relates to a disaster's outcome in terms of loss of life and property. Hence it becomes imperative to assess the built environment and minimize the seismic impact comprehensively. The currently available literature focuses on the individual elements of the built environment operating as independent domains of research. However, this article emphasizes the need to understand the built environment from an ecosystem perspective where each element interacts to produce a comprehensive disaster effect. Utilizing urban planning as a seismic risk reduction tool, this paper identifies the elemental composition of the urban environment and proposes a framework to assess the Built Environment Vulnerability (BEV). The study functions at the mid-scale resolution and introduces two new concepts, Discrete and Systemic Vulnerabilities. A total of 1107 buildings and 134 kilometers of road have been surveyed, and object-oriented analysis is carried out in six neighborhoods of Siliguri Municipal Corporation, India. The results are the differential BEV pre and post-earthquake across the six neighborhoods corresponding to their different built characteristics.