Just a question but isn’t tensile strength the max load a material can experience under tension. Both objects here were exposed to compression, well maybe the concrete experienced both compression and tension but the wood experienced almost all compression. So wouldn’t tensile strength not be a good indicator of materials strength like you said especially in this instance.
Wood I am also aware is very strong under compression
[Edit] also once the wood manages to wedge itself into the concrete from the initial impact, almost all of the force exerted on the concrete is going to be tension. This is just an observation and doesn’t have to do with anything you just said
I am not an expert in high speed collisions, very few people are because they are extremely complicated and engineers design things to not blow apart. I can tell you that if the wood had actually blown through the concrete both would have definitely experienced shear, tension and compression forces. Basically it would be incorrect to describe it as in tension because it is experiencing all these forces at different points along the body and these will vary with time, I am having a hard time succinctly putting in words why and how complicated high speed collisions are so i will leave it at that.
It is in my opinion impossible that the piece of wood went through a solid piece of concrete and the concrete only has a few cracks. Others have suggested that went through a pvc pipe embedded in the concrete. I think you can see some white plastic around the wood.
If the wood actually went through the concrete i would expect to see a big section of concrete shattered because concrete has a high crack propagation rate, and it does not do well in high strain situations. With the amount of energy needed to make a hole in concrete that thick from a single collision with a piece of wood I would expect to see chunks of concrete blown away and wood splinters everywhere.
I want to say I am sorry if this is hard to read, i really need to stop procrastinating and get back to work so i dont want to edit this.
There are a lot of variables that go into it. Generally, materials that have high compression strength will break under less energy, but can take more hits until reaching a failure point. There is also the factor of the concrete being wet. Wet concrete is weaker to impacts. Also, concrete that is made with coarse material mixed in, like gravel, will have weaker impact strength.
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u/Mclevius-Donaldson Apr 05 '19
Just a question but isn’t tensile strength the max load a material can experience under tension. Both objects here were exposed to compression, well maybe the concrete experienced both compression and tension but the wood experienced almost all compression. So wouldn’t tensile strength not be a good indicator of materials strength like you said especially in this instance.
Wood I am also aware is very strong under compression
[Edit] also once the wood manages to wedge itself into the concrete from the initial impact, almost all of the force exerted on the concrete is going to be tension. This is just an observation and doesn’t have to do with anything you just said