In this talk I will present my PhD findings on the loading behaviour of blast ingress through façade openings into structures, and its implications for interior pressure loading. The current international benchmark, UFC 3-340-02, is evaluated against a validated computational fluid dynamics (CFD) approach (Ãå±±ÂÖ¼é’s ProSAir). ProSAir was first validated against historical experiments and a new dedicated test, reproducing interior pressure-time histories with an average accuracy of ±10%.
A comparative study of 720 CFD simulations spanning all five UFC predictor variables was then conducted. The results map where UFC predictions deviate: overestimates of interior side-wall loading up to 1100%, and a lack of conservatism for back-wall loading at larger scaled distances. These discrepancies indicate that UFC guidance can lead to both unnecessary strengthening and, in some cases, potential under-protection.
To address this, a fast-running engineering model (FREM) was developed using regression models on the CFD dataset and verified against an additional 420 cases. With the same five predictor variables, FREM achieves ±20% accuracy with an average standard deviation of 7.5%.
Application to representative design problems (420 cases) indicates average material savings of 50% on average (and up to 70%) compared with UFC-based designs, while maintaining appropriate safety margins. The talk will outline the evaluation methodology, key findings, and practical guidance on adopting FREM, and will discuss implications for updating UFC and related national practice.
The Terrorism Risk Assessment, Modelling and Mitigation Seminar Series (TRAMMSS) is a virtual seminar series focused on technical topics related to terrorism risk assessment, and modelling, including blast modelling and response; IEDs; vehicles as weapons; CBRN; big data for risk assessment, security and screening; and associated mitigation measures.
Alex Eytan has more than 20 years of practical experience in the design of protective structures and systems. Following 9/11 he was managing Israel military trilateral joint research programmes with US and UK government agencies into deployable protective solutions from blast effects. He has led designs of US DoD and DoS facilities in Iraq and Afghanistan before setting up his own consultancy practice.
In recent years Alex has completed numerous risk and damage assessments of embassies, government buildings, corporate headquarters, data centres, airports and VIP residences, and has designed multiple ballistic protective solutions to counter terrorist forces in the UK, Europe and the Far East. Alex is currently completing his PhD at Cranfield Defence and Security.
A comparative study of 720 CFD simulations spanning all five UFC predictor variables was then conducted. The results map where UFC predictions deviate: overestimates of interior side-wall loading up to 1100%, and a lack of conservatism for back-wall loading at larger scaled distances. These discrepancies indicate that UFC guidance can lead to both unnecessary strengthening and, in some cases, potential under-protection.
To address this, a fast-running engineering model (FREM) was developed using regression models on the CFD dataset and verified against an additional 420 cases. With the same five predictor variables, FREM achieves ±20% accuracy with an average standard deviation of 7.5%.
Application to representative design problems (420 cases) indicates average material savings of 50% on average (and up to 70%) compared with UFC-based designs, while maintaining appropriate safety margins. The talk will outline the evaluation methodology, key findings, and practical guidance on adopting FREM, and will discuss implications for updating UFC and related national practice.
The Terrorism Risk Assessment, Modelling and Mitigation Seminar Series (TRAMMSS) is a virtual seminar series focused on technical topics related to terrorism risk assessment, and modelling, including blast modelling and response; IEDs; vehicles as weapons; CBRN; big data for risk assessment, security and screening; and associated mitigation measures.
Alex Eytan has more than 20 years of practical experience in the design of protective structures and systems. Following 9/11 he was managing Israel military trilateral joint research programmes with US and UK government agencies into deployable protective solutions from blast effects. He has led designs of US DoD and DoS facilities in Iraq and Afghanistan before setting up his own consultancy practice.
In recent years Alex has completed numerous risk and damage assessments of embassies, government buildings, corporate headquarters, data centres, airports and VIP residences, and has designed multiple ballistic protective solutions to counter terrorist forces in the UK, Europe and the Far East. Alex is currently completing his PhD at Cranfield Defence and Security.
Who should attend
This seminar is open to guests from outside Cranfield, who may work in academia, research, or industry. Due to the potentially sensitive nature of this seminar series, guests should be able to show that they are affiliated with an appropriate bona fide organisation.Cost
The event is free of charge, but participants must register for the TRAMMSS mailing list in advance.How to register
To attend this seminar, you must register for the TRAMMSS mailing list via the . Upon mailing list registration, you will be sent a second link to register for the webinar itself.Further information on the TRAMMSS community can be found on the main website at cranfield.ac.uk/TRAMMSS
