Blast-resistant buildings can provide refuge to personnel, reduce injuries and protection of contents during explosive devices attacks.
Blast-resistant buildings are engineered for the loads induced by explosions. Buildings must be designed so that they will not collapse or cause injury or death within the building due to blast overpressure. The wall panels are typically made of steel-reinforced concrete which will reflect pressure back into the room rather than breaking windows and doors. Depending on the proximity to the explosion, lights may flicker or break, but do not enter into what is called “ductile mode”. This means objects inside a relatively protected structure will move with stress waves but return to their original shape once outside of it. The last effect depends on geometry; because blast-resistant buildings are usually circular in shape, objects inside take less damage. It is not possible to protect against every type of device detonation, but it can be done for most threats.
Blast-resistant buildings also allows the same space to be used more than once.
Areas that are no longer safe due to fragmentation or secondary explosions could easily be cleaned up and refurbished while personnel are still using the area immediately around the blast site.
Repairing a section after an explosion requires less time since doors and windows do not need to be replaced which speeds up reconstruction efforts. For example, if one room was destroyed, there might only need 10 minutes of work compared with several hours if roofs needed replacement or walls needed repair. Blast-resistant buildings help to reduce construction time and cost since less materials will be damaged or need to be replaced in the event of a blast.
Blast-resistant buildings are often used for homes, schools, hospitals, factories.
Blast-resistant houses provide protection from the threat of terrorist attack with an explosion from outside such as a car bomb detonating beside it. In addition to protecting against explosives threats, they can provide protection against weather hazards such as tornadoes and hurricanes, or earthquakes.
A stronger number is assigned to the structure if it has been designed under blast resistance standards that consider its function along with overall structural design. The most common method for determining a blast rating is through an engineering study that takes into account specific criteria based on type of building and location.
For example, a school in a high-risk area or a nuclear power plant in an earthquake zone would receive a higher number.
How much protection a building has in contrast to the outside environment is not always apparent from viewing the building itself. Blast resistance ratings can be found on many buildings and usually takes into account critical elements that influence its response under blast conditions such as reinforcement, thickness of wall panels and location within the structure. The table below provides examples of common blast resistance ratings:
Overexplosion hazard suppression systems are used to reduce damage associated with explosive materials by controlling or quenching unplanned explosive events at their source. These include:
Common features of a blast-resistant building:
The structure has special reinforced concrete and structural components that increase its strength.
There is no or little glass to break and shatter into manageable pieces.
Doors, door frames and window frames are heavy duty and won’t bend in the event of an explosion. The doors may be up to 4 inches thick depending on their proximity to a potential blast site. Some buildings have walls made from steel plate instead of the typical masonry brick construction which allows for greater flexibility during an explosion while still providing protection from surrounding debris.
There is extra reinforcement around possible impact points such as windows, doors and corners where two walls meet. These areas will likely sustain more damage than other parts of the structure.
There is a drainage system to direct any water and debris away from the building. For example, if there was an explosion in front of the building, there could be significant damage to windows and doors causing them to crack or shatter. The drain can help prevent this by diverting rainwater away from these openings which prevent additional damage and allows for easier cleanup efforts after an event occurs.
