Played some Duke Nukem and I noticed again how much I like exploding those cracked walls. I set to create a similar effect, only the result is slightly different.
Here's a video of it for those of you who are lazy.You will have to adjust the func_breakable's Strength property, I put it to 1 for demo purposes. The sound is included too in 16bit and 8bit format.
Notice: I used Sledge for this. Please delete the trigger_auto which triggers the trigger_push and check the trigger_push's "Start off" flag. For some reason Sledge didn't allow me to do that.