Carta del editor asociado
Resumen
My interest in blast loading stems from the terrorist attack on the parking building of Terminal T4 at Madrid–Barajas Airport, which took place on Sunday, December 30th, 2006, and almost completely destroyed Module E of the parking structure. The attack claimed two lives. The explosive charge is estimated to have been between 500 and 800 kg. I visited the site twice that day because FHECOR had designed the structure. When I first witnessed the devastation—something for which no one had prepared me—I was overwhelmed. The following day, with a clearer mind, I returned to inspect the damage more closely and observed several unusual failure mechanisms rarely seen in structural engineering, induced by load reversal, particularly the clean separation of the slab–column connections. This experience, both traumatic and transformative, is what has ultimately led me to present this special issue of Hormigón y Acero devoted entirely to this subject.
This issue covers a broad range of topics, from theoretical developments and experimental research to practical engineering experience.
On the theoretical side, Wilhelms et al. introduce a new concept: Energy–Power (E–P) diagrams as an alternative to the traditional Pressure–Impulse (P–I) diagrams. These diagrams represent the combinations of energy and power that a structure can withstand, making it possible to assess structural performance under different blast scenarios in a manner analogous to the axial force–bending moment (N–M) interaction diagram. The principal advantage of the E–P diagram is that, for a given blast scenario, these quantities can be determined directly from the scaled distance and geometric considerations, whereas the P–I approach requires a dynamic analysis.
This paper is followed by four contributions with a strong experimental component. Chiquito et al. present a blast test on a simple steel structure designed to remain within the elastic range, with the aim of estimating the blast loading from the measured and predictable structural response. Colombo et al. address the interaction between blast and fire in tunnels, using immersed tunnels proposed for crossing the Norwegian fjords as a practical case study. Cendón et al. present an experimental campaign involving explosive charges applied to high-strength self-compacting concrete slabs reinforced with steel fibres. Finally, Aminou et al. investigate the energy absorption capacity of a brittle mineral foam used to protect a metallic specimen representing a structural element.
The issue concludes with two papers focused on practical engineering applications. Rodríguez et al. present their extensive professional experience through a series of real blast incidents that they have investigated as part of INTEMAC's forensic and structural assessment activities. Finally, Rodríguez describes the methodology currently applied in engineering practice for the analysis of accidental blast scenarios in industrial facilities.
Taken together, these contributions provide a comprehensive overview of a subject that, unfortunately, is becoming increasingly relevant due to technological developments such as the widespread availability of drones. Structural engineers must therefore incorporate the analysis of blast effects into their professional expertise.
