Yes, of course it has. I'm certainly not an expert, but the plants are operating on a set of risk calculations based on assumptions about their designs. If one of the safety assumptions are challenged, you have to shut the reactors down and address it.

Now, I'm sure you can find instances where this was not done. But if you just vaguely follow nuclear news around the world, nuclear power plants do indeed have correlated shutdowns. The most widely reported one in the past decade probably started with the accident at the Fukushima power plant. But there are many examples of smaller ones.