phys.org, July 2016
"Researchers at MIT are making fluorescent polymer gels that change color when they're shaken, heated, exposed to acid, or otherwise disrupted. Given such a response, these novel materials could be effective sensors for detecting changes in structures, fluids, or the environment."
Buildings are not alive, so they don't heal themselves. It's hard for us to find out what's wrong with them, because most of their critical parts have been made invisible according to our cultural-architectural preferences.
But now, if there's structural damage in a place that's been doped with pressure-sensitive colorgel, we can see it.