The influence of obstacle geometric fidelity on blast wave propagation: a reduced-scale case study examining the role of the grain siloes in the 2020 Beirut explosion
The influence of obstacle geometric fidelity on blast wave propagation: a reduced-scale case study examining the role of the grain siloes in the 2020 Beirut explosion
In the field of blast protection engineering, it remains challenging to validate large, complex numerical models and the implications of modelling assumptions relating to how structures are represented (e.g., geometric fidelity) are not well understood. This paper presents experimental work addressing these two issues, in the context of the 2020 Beirut explosion, which remains an important case study for understanding urban blast effects. A series of reduced-scale (1:250) blast tests examined shielding effects caused by the Beirut grain siloes and investigated the influence of the siloes’ geometric fidelity on blast loading. Rigid obstacles were constructed at two geometric fidelities: “rectangular” (i.e., cuboid), and “accurate”, with closer resemblance to the siloes. Pressure gauges were mounted at multiple locations but at fixed blast scaled distances to examine blast-obstacle interaction behaviour. Additionally, Viper::Blast was used to perform computational fluid dynamics analyses of the tests. Experimental findings confirmed significant shielding (reduced pressure and specific impulse) locally behind the siloes (Z<3 m/kg1/3), although models indicated that these effects ceased further afield (Z>5 m/kg1/3). Overall, blast wave parameters did not exhibit significant differences between the rectangular and accurate representation of the siloes geometry, except for minor differences (+/-10%) in peak overpressures in localised zones. Numerical models confirmed that these discrepancies were caused by differing blast wave scattering, diffraction and superposition behaviour attributed to the siloes outer geometry. The results suggest that city-scale blast loading analyses can yield reliable results through idealising structures as simplified, cuboidal obstacles. These findings will be of direct relevance to blast protection practitioners and researchers concerned with modelling urban blast scenarios.
Denny, Jack
7bd3e650-6c4e-4149-b408-2166e377b216
Farrimond, Dain
069e1271-9715-4250-af72-a3840a4ff031
Gabriel, Sherlyn
3d919697-e2ee-4bc1-b535-01ea6ee331f7
Chung Kim Yuen, Steeve
97f87574-96ea-4d0a-8875-dac780229bed
Rigby, Sam
e571d216-3bb1-4de7-b837-67b84cfe84ed
Al-Hajj, Samar
a48b9d68-2dc0-40ca-9bcd-a9df902893ce
Langdon, Genevieve
bfdfdec0-401c-4839-8a68-8c8c46ddf667
2 September 2025
Denny, Jack
7bd3e650-6c4e-4149-b408-2166e377b216
Farrimond, Dain
069e1271-9715-4250-af72-a3840a4ff031
Gabriel, Sherlyn
3d919697-e2ee-4bc1-b535-01ea6ee331f7
Chung Kim Yuen, Steeve
97f87574-96ea-4d0a-8875-dac780229bed
Rigby, Sam
e571d216-3bb1-4de7-b837-67b84cfe84ed
Al-Hajj, Samar
a48b9d68-2dc0-40ca-9bcd-a9df902893ce
Langdon, Genevieve
bfdfdec0-401c-4839-8a68-8c8c46ddf667
Denny, Jack, Farrimond, Dain, Gabriel, Sherlyn, Chung Kim Yuen, Steeve, Rigby, Sam, Al-Hajj, Samar and Langdon, Genevieve
(2025)
The influence of obstacle geometric fidelity on blast wave propagation: a reduced-scale case study examining the role of the grain siloes in the 2020 Beirut explosion.
Shock Waves.
(doi:10.1007/s00193-025-01241-5).
Abstract
In the field of blast protection engineering, it remains challenging to validate large, complex numerical models and the implications of modelling assumptions relating to how structures are represented (e.g., geometric fidelity) are not well understood. This paper presents experimental work addressing these two issues, in the context of the 2020 Beirut explosion, which remains an important case study for understanding urban blast effects. A series of reduced-scale (1:250) blast tests examined shielding effects caused by the Beirut grain siloes and investigated the influence of the siloes’ geometric fidelity on blast loading. Rigid obstacles were constructed at two geometric fidelities: “rectangular” (i.e., cuboid), and “accurate”, with closer resemblance to the siloes. Pressure gauges were mounted at multiple locations but at fixed blast scaled distances to examine blast-obstacle interaction behaviour. Additionally, Viper::Blast was used to perform computational fluid dynamics analyses of the tests. Experimental findings confirmed significant shielding (reduced pressure and specific impulse) locally behind the siloes (Z<3 m/kg1/3), although models indicated that these effects ceased further afield (Z>5 m/kg1/3). Overall, blast wave parameters did not exhibit significant differences between the rectangular and accurate representation of the siloes geometry, except for minor differences (+/-10%) in peak overpressures in localised zones. Numerical models confirmed that these discrepancies were caused by differing blast wave scattering, diffraction and superposition behaviour attributed to the siloes outer geometry. The results suggest that city-scale blast loading analyses can yield reliable results through idealising structures as simplified, cuboidal obstacles. These findings will be of direct relevance to blast protection practitioners and researchers concerned with modelling urban blast scenarios.
Text
Manuscript - Accepted Version
- Accepted Manuscript
Restricted to Repository staff only until 18 June 2026.
Request a copy
More information
Accepted/In Press date: 18 June 2025
Published date: 2 September 2025
Identifiers
Local EPrints ID: 503556
URI: http://eprints.soton.ac.uk/id/eprint/503556
ISSN: 1432-2153
PURE UUID: 43b3736a-edd5-4429-8b10-a8aae77e1210
Catalogue record
Date deposited: 05 Aug 2025 16:39
Last modified: 10 Oct 2025 01:57
Export record
Altmetrics
Contributors
Author:
Dain Farrimond
Author:
Sherlyn Gabriel
Author:
Steeve Chung Kim Yuen
Author:
Sam Rigby
Author:
Samar Al-Hajj
Author:
Genevieve Langdon
Download statistics
Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.
View more statistics