hide
Free keywords:
-
Abstract:
Building exposure, that is, characterization of buildings number of people occupying it and its replacement cost, for a given region or area, is one of the primary components when determining building risk due to a hazard or group of hazards.
We have developed an exposure model for Japan at the municipality level. This model is entirely derived from open building data (e.g., census) and resulting in an open inventory of uniformly defined building parameters available for risk assessments. The Japanese land and housing database (ESTAT: https://www.e-stat.go.jp/en) provides information about building types and their number, dwelling type, their number and size, tenure type, construction material type, year of construction, number of stories, persons per dwelling and size of dwelling (area in square meters). Different combinations of building parameters were mapped to building classes based on the taxonomy of the Global Earthquake Model (GEM).
Quality of the model is greatly affected by the availability of building parameters and their survey quality in the census data, thus limiting the flexibility and versatility of the model to be up- or down-scaled.
Despite the limitations, the model gives a very clear snapshot of distribution of regional building classes and their possible count. Also representing an open catalogue of rules for mapping Japanese building attributes and, in doing so, creates an opportunity for the scientific and non-scientific community to collaborate. We welcome corrections and expansion of individual aspects of the aggregated exposure model and like to encourage the development of such open aggregated exposure models for other countries.