Crash-Aborbing Concrete Review

Crash-Absorbing Concrete

On average there is an 42,000 road deaths in the United States per year.  These crashes causes untold amount of stress on families across the nation and costs the United States over 300 billion dollars a year.  Many of these deaths could be prevented with the use of the right engineering materials utilized in the correct way.  

One of ways that engineers try to reduce head on collisions, which usually result in fatalities, is the use of barricades to prevent traffic, that loses control, to enter into oncoming traffic.   In the past, engineers have utilized “hard” barriers to prevent this from happening.  The barriers could be anything from steel cables, metal guardrails, and solid concrete medians.  These approaches were affective at keeping vehicles from entering into oncoming  traffic, but they have on major downside.  This is that there is relatively no give when vehicles collided with them.  This causes more injuries and fatalities to occur to the vehicle hitting them.

This is where crash-absorbing concrete comes into play.  It is also known as aerated concrete.  It is made by using excess amounts of water in the concrete mix design.  This makes it very hard to form when putting it in place but once it starts to harden the excess water that is in the concrete begins to evaporate out.  This leaves a large amount of air voids in the concrete itself making it almost like foam.  With the air voids in the concrete it becomes very easily deformable so when vehicles crash into it a lot of the energy is absorbed by deforming the concrete instead of expending that energy back into the vehicle which causes the injuries and fatalities.  You can think of it this way, would u rather run into a solid concrete wall or into a wall of pillows.  I for one would rather run into the wall of pillows.

It has taken engineers quite a few years and a lot of testing to get the mix just right so that it can easily be formed while still deforming at the specified loads that are needed for all types of vehicles.  One of the main problems that they ran into was with the different types of vehicles that are on the road today.  A semi is going to take a lot more firm of concrete to stop it from going into head on traffic than say a geo metro will.  This means that they had to a lot of testing to get it right.  

Another place where engineers are thinking about using this product is at the end of airplane runways.  It would be used at the end of the runways to stop planes from overshooting the runway.  They would actually lay the crash-absorbing concrete just like you would the runway, but when the airplane rolled over it the concrete would give way absorbing the forward momentum of the airplane.  It would be the equivalent of driving into deep sand.  This is better than using the methods that they currently use because it requires no maintenance or upkeep once it is in place.

Overall I think that this is a very good product that should be implemented sooner rather than later so it can start saving lives and money.  It is a very simple approach to a very large problem, but most of the time simple is usually better.