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Section
Lessons learned
What we have tested or seen in the field.
- Engineering · Blast test
“Nothing” as protection
Air volumes to break up the wave of a contact charge: prototypes neither perforated nor projected.
· Patrick MartinLinkedIn ↗ - Engineering · Blast test
Door rebound, a little-known phenomenon
The energy the leaf releases on the way back can tear out bolts and hinges.
· Patrick MartinLinkedIn ↗ - Engineering · Blast test
Measuring to update the calculation
Our own measurement chain: 96% agreement between measured and calculated pressures.
· Patrick MartinLinkedIn ↗ - Blast test
“Concrete” shelter 1, lightweight shelter 0
12 kg of TNT at 5.5 m: no displacement, no deformation, and a door that still opens.
· Patrick MartinLinkedIn ↗ - Engineering
The danger of “standard” solutions
A study rather than a standard solution: keep the existing wall, change the joinery.
· Patrick MartinLinkedIn ↗ - Engineering
Quantifying the threat, then the protection
Define the accepted threat, then quantify the resistance of the structures through simulation.
· Patrick MartinLinkedIn ↗
Section
Before you ask for a quote
What to know before writing a specification or requesting a quote.
- Engineering
The “7-bar door”: where does it come from?
A requirement born of one specific case, applied everywhere as a shortcut: start from the real scenario.
· Patrick MartinLinkedIn ↗ - Engineering
Anti-blast — but against which blast?
The same charge, very different effects depending on the setting: start from the scenarios before designing.
· Patrick MartinLinkedIn ↗ - Engineering
Buried shelters: Archimedes and Murphy
Groundwater lifts the shelter, and water eventually gets in: burying a shelter calls for a study.
· Patrick MartinLinkedIn ↗ - Engineering · Blast test
Which door for a shelter?
After the explosion, the door must still open, stay airtight and control its rebound.
· Patrick MartinLinkedIn ↗ - Engineering
Shelters and CBRN protection
Never perfectly airtight, a shelter protects itself through overpressure: how many people, for how long?
· Patrick MartinLinkedIn ↗ - Engineering
Glazed walls: the wall, the frame, the glazing
Hardening the glazing is not enough: the wall, the frame and their anchorages must hold.
· Patrick MartinLinkedIn ↗ - Engineering · Blast test
Anti-blast: what product sheets really say
A pressure alone qualifies nothing: the duration, or the distance, is needed.
· Patrick MartinLinkedIn ↗
Section
Understanding blast
A concept explained, a misconception corrected.
- Engineering
Impulse is not a dirty word
7 bar can hide an impulse ten times greater: a pressure is never specified on its own.
· Patrick MartinLinkedIn ↗ - Engineering
No need, there’s a barricade!
A barricade stops fragments, not the shock wave: it wraps around it and reflects behind.
· Patrick MartinLinkedIn ↗ - Engineering
The CBRN filter: where should it go?
By trapping radioactive dust, a shelter’s filters can irradiate its occupants.
· Patrick MartinLinkedIn ↗ - Engineering
Can a shelter be lightweight?
Without mass or anchorage, the shelter is thrown, and its shell strikes the occupants.
· Patrick MartinLinkedIn ↗ - Engineering
Zero density — or negative!
To close before the wave, a grille would need zero density.
· Patrick MartinLinkedIn ↗ - Engineering
Blast walls: types and limits
At the top of the wall, the wave bends and resumes its course into the area thought to be sheltered.
· Patrick MartinLinkedIn ↗
Section
News
An event seen through our eyes.