Deterministic consequence assessment of urban spaces due to blast loading
In this paper, the physical background and the usability aspects of the expert software BREAS (Blast Response Assessment of Structures) are presented. This comprehensive tool evaluates the structural initial response of buildings to blast loading neglecting the impact of potential fragments. The results are visualized in a user-friendly three dimensional graphical user interface. Arbitrary building configurations can be considered. Typical application areas are field camp situations or military operations in urban terrain (MOUT). Different building materials and pre-defined object types are implemented, such as masonry, reinforced concrete, (security) glass and wall panels or window elements of typical used residential buildings or containers. The tool includes an optional application of security enhancement measures, e.g. blast resistant walls or innovative retrofit materials. State-of-the-art engineering models are used for the nonlinear structure evaluation. For the hazard analysis of an arbitrary blast loading scenario, two different approaches are implemented. The first one uses semi-empirical assumptions and allows a fast assessment of the external blast loading. The second option includes an interface to an explicit finite volume scheme with automatic mesh refinement. This CFD tool has been seamlessly incorporated into the software and offers more precise information concerning complex blast wave propagation. The calculation of an actual conducted terroristic explosive event in an urban environment is used for validation of the software and underlines the forecasting ability of the software. The tool BREAS is developed for/in cooperation with the Technical Center for Protective and Special Technologies (WTD 52) and the German Armed Forces (BAIUDBw Infra II 2).