Explosions in a denser urban environment

Research Project, 2020 – 2023

With the aim of making attractive land space available for further development, there is today a desire in many cities to implement a densification of the existing urban environment. However, such densification, e.g. street overbuild, leads to a reduced free distance between buildings and transport route, which results in increased requirements against exceptional accidents such as explosions. To create an optimal overall solution for such an accidental scenario it is necessary that the three sub-areas risk management, explosion load and structural response are properly coordinated.

In today's handling of explosions, there are significant shortcomings among both risk analysts and structural engineers. A contributing reason for this is partly that communication between these two groups is inadequate and partly that the level of knowledge about explosions is often insufficient. An explosive load creates an intense load pulse of short duration that can cause a structural response that differs significantly from that normally obtained under static load. This puts special demands on the design of explosion loaded structures, for which there are currently no adequate guidelines. This is of interest for e.g. explosion in tunnels/street over build, bridge columns, or protective piers subjected to impact. It may also be applicable to buildings that may be affected by the proximity to transport routes.

The overall aim of the project is to contribute to increased national competence development in the field of explosions. One of its goals is to bridge the gap between risk analyst and structural engineer by clarifying the link between an explosion and its consequences. However, the intention is not to work with risk per se, but rather with the development of tools that can then be used in risk management. Other objectives are to develop simplified methods for determining the explosion load and to improve existing methods for determining the resistance of a structure subjected to an explosion load. The focus will be on developing simplified computational models for explosion loads and structural response, in order to approximately take into account various types of complex phenomena, and thereby make these available to a wider range of structural engineers.