If nothing is moving then you can patch but if these change over 24 hours or 12 months then a permanent fix will be more complicated.
So, how to find out if these gaps are expanding or contracting, how much and how fast? I guess you can use drill bits as feeler gauges so you'll be able to see small changes.
And with what force? If you fasten them will a new crack open elsewhere?
That last pic is strange. It can't be compression damage because the whole surface would have buckled. Maybe something is trying to get out, a pipe, maybe.
Last edited by Wuzzat?; 03-10-2014 at 08:10 PM.