I did martial arts for years and often helped out with the classes as an adult. We used to buy the cheapest concrete brick/paver we could get for breaking. Something similar to this:
There is a lot of variance in bricks. And honestly a lot of the cheap ones would break if you dropped them, or loading and loading them in the van...
Not to mention people would accuse us of baking them, or freezing them, leaving them outside for months or years, all kinds of stuff. But honestly we would buy a bunch of them from the home improvement store on the way to the demo at the mall or a school. You'd be surprised at how easily you can break one with the simple tap of a claw hammer.
It's just physics. The longer the brick, the easier it will break. Some demo rocks are much longer. The trick is to hit it fast, use the smallest impact point you can, and follow through. If you don't follow through you won't even be able to break a pine board. Theres some kind of psychological thing prevent most people from punching through a target, whether it's a brick, punching bag, or a board.
Walls generally have studs that are 1.5" wide every 16", so more than 90% of points on a wall are not in front of a stud. You do need to punch a few inches away from the stud to account for the width of your hand and to get enough leverage to break the drywall, so maybe expand the width of the hand-break-zone from 1.5" to 8", and you've got around a 50% chance that punching a random spot on the wall avoids a stud.
> so more than 90% of points on a wall are not in front of a sud
That would depend on the wall length, no?
For example, a 1.5"-3" wall has 100% of points on a stud. Also many (most?) traditional residential constructed walls have end plates, at least one top plate, a bottom plate, fire blocking, support, kings, sisters, cripples, jacks, headers, etc.
Anyway, I think its probably safe to say more than 10% of the surface has wood or some other object behind it on many walls, and unlikely that you could "do the math on this" without surveying data.
The top and bottom plate are unlikely to get punched, as you're going to tend to punch towards the middle height wise. Fire blocking became required by code in maybe the 80s or definitely in the 90s; there's a lot of older housing that may not have it. Also, it seems like a lot of this punching or kicking of walls happens near doorways, you're going to tend not to punch the wall near the doorframe, and if you go in maybe one shoulderwidth, you're not likely to hit a stud.
One of my friends had the "brilliant" idea of playing "drywall roulette." In a room about to be demoed, run headfirst into somewhere near the center of the wall. First person to hit a stud loses.
I punched a wall while mad and put a hole in the drywall. I didn't plan where I was going to hit it. I'm not proud I did that though. Firstly, for losing my temper, which is not who I strive to be. Secondly, it's obviously weak material. I'm sure a lot of people have.
I used to have a rage problem until about 5 years ago. I broke a number of phones in the few years before that, so I bought a rugged one. In my last ever bout of rage, I threw the phone at the wall. I expected the phone to break, but instead it made a hole in the wall. I spent ages researching how to fix it and in the end ended up using quickfill and painting over it several times. From that point onwards, I've always preferred handstand pushups when I'm feeling agitated.
I assume selection bias is in play: for every post on the internet there are many more who did break their hand and ended up in ER, they were just too ashamed to talk about it.
A kid I went to junior high school with said that he put his head through a wall--he was wrestling, and the other guy threw him. I was a bit skeptical, because I then lived in a house with plaster and lath walls, and had not encountered drywall. But I expect he told the truth
https://www.homedepot.com/p/16-in-x-8-in-x-1-75-in-Pewter-Co...
There is a lot of variance in bricks. And honestly a lot of the cheap ones would break if you dropped them, or loading and loading them in the van...
Not to mention people would accuse us of baking them, or freezing them, leaving them outside for months or years, all kinds of stuff. But honestly we would buy a bunch of them from the home improvement store on the way to the demo at the mall or a school. You'd be surprised at how easily you can break one with the simple tap of a claw hammer.
It's just physics. The longer the brick, the easier it will break. Some demo rocks are much longer. The trick is to hit it fast, use the smallest impact point you can, and follow through. If you don't follow through you won't even be able to break a pine board. Theres some kind of psychological thing prevent most people from punching through a target, whether it's a brick, punching bag, or a board.
Drywall, however, is an exception to this rule.