There was some news years ago that there was a bacteria that could hold the key to ensuring modern rebar reinforced concrete could repair itself over time: http

There was some news years ago that there was a bacteria that could hold the key to ensuring modern rebar reinforced concrete could repair itself over time: http://www.nydailynews.com/news/national/concrete-fix-thanks-bacteria-article-1.2224769 http://www.nydailynews.com/news/national/concrete-fix-thanks...