Posts by SO failed us all... Bye...
I think I can now answer my own question, having come across some decent references I hadn't found before asking it. I found the equation for the gravitational strain $h$ - the proportional change ...
Answer
I wish to create a world such that it can support the following plot point: the world experiences gravitational waves that are directly noticeable to the human population (i.e. they can feel or see...