One drive down a local highway or high traffic roadway and it becomes very obvious that most states can't keep up with how fast our roads are deteriorating. However, a newly developed self-repairing concrete may be able to offer those countless road crews a much needed hand.
The idea came from the mind of Michelle Pelletier of the University of Rhode Island. Pelletier found that by including microencapsulated sodium silicate in the traditional concrete mixture, the hardened product was about to regain up to 26% of its original strength after being fractured. It should be noted that this figure was calculated using only 2% sodium silicate in the mixture. Pelletier believes using more of the silicate in the concrete could yield even higher numbers.
Concrete Strength Testing
The science behind the self-repairing concrete is fairly simple. When the concrete fractures, the pressure also breaks the capsules containing the sodium silicate, releasing it into the concrete. The silicate then reacts with the calcium hydroxide normally found in concrete to create a calcium-silica-hydrate. This will fill the cracks and act as a binder between pieces of already set concrete.
Most promising about this new concrete is how cheap it will be to manufacture. The addition of sodium silicate will not drive the cost up like some of the other solutions proposed in the past and since little will change in the handling of the mixture, wide-spread adoption would be easy.
The University is planning on more extensive testing of the new concrete in the upcoming year.University of Rhode Island