UDK (and UE4 also with the simulate option) lets you pack meshes into the same space. After changing the physics type it creates a kind of dramatic explosion effect (as the meshes repel each other). So its similar to an apex setup (if you can’t get apex working).
You can even use the scale option to shrink the meshes until the explosion is needed. There are a couple of caveats to this. The actor / component that the meshes are attached to may be affected (thrown about) by the explosion, unless you temporarily disable its movement.
Also since you’re not actually breaking any meshes, you’ll have to design the static mesh chunks or compress them differently each time (change transforms) in such a way as they look believable when separated. I’ve used this in UDK a lot, and while it doesn’t have the finesse and options of apex maybe, it can look effective, especially the bigger the explosion.