The formula is PI times R-squared times 92,000. No dividing. At any rate 6000 +/- LBS is 3 tons. If a crossmember has 4 bolts per side, the strength is approx. 12 tons per side. Should be adequate for most speed bumps. The numbers are so high it does not matter if you are talking shear, tensile or yield.
Yeah I seem to figure out how to make something more complicated than it needs to be. Both methods come up with the same answer. Thanks for the correction.
