Beyond the issues the article acknowledges, and the misleading implication that this would help fix existing roads/bridges, I see two large question areas: * T

Beyond the issues the article acknowledges, and the misleading implication that this would help fix existing roads/bridges, I see two large question areas: * The claim is that the spores would be "dormant" until cracks appeared and brought water to them. How exactly does that happen? What ensures the calcium carbonate grows ONLY in the cracks? Why would this not lead to uneven/bumpy roads? * They say that the spores would probably get crushed in existing concrete blends, but maybe we could add air bubbles to the mix. I'm not a material scientist, but I'd guess that taking something with 1 micrometer holes and making them into 4 micrometer holes would have impact on the resulting material. I'm not saying that the research isn't worth pursuing, but it is a bit of a smell that such questions aren't even acknowledged in the article.