# I beam stuff

Yesterday I made an I beam out of cardboard and compared it against just 6 strips of cardboard. The I Beam held up more weight than the pieces of cardboard. I don’t have anything else to say so I did some more research on the I beam and found out that there is a formula to figure out how strong the I Beam will be compared to other shapes. This is called area moment of inertia, and, yes I memorized this, the formula for an I beam is, assuming the I beam is on it’s x axis (I’ll put a picture down below of the I beam) is : I sub x = (a h^3/12) + (b/12)(H^3-h^3). If on the y axis, then it is  : I sub y = (a^3h/12) + (b/12)(H-h). The number you get at the end is just a representation that you can use to compare with other shapes. The a is the width of the web, h is the height of the web, H is height of the whole thing, and B is the width of the flanges. Why 12? It’s derived from physics, and I’m not going try to figure that out. The rectangle cardboard is more simple it is I sub x = bh^3/12 and I sub y is b^3h/12. b and h is base and height. The higher the number you get, the more weight the beam can withstand. The website I learned this from is called Engineeringtoolbox.com and it has lots of other interesting stuff about engineering.

I beam picture