A more correct calculation will show that only a portion of the footing area will bear on soil. Referring to the image above, simple statics will tell you that the other end of the footing experiences soil in tension which is of course invalid. Now if you can kindly go to this post of mine where I explained flying footings in detail.īut before you can say that a footing is flying, you have to find out whether an end is in tension. Flying footings if you remember are footings where because of significant uplift due to large bending moment to axial load ratios, is experiencing zero soil bearing pressure on certain parts of the footing area. I just got hyped when I was able to prove that it is capable of considering the case of flying footings.
If you don’t have a finite element analysis software and you don’t have the luxury of time to create a spreadsheet from scratch, Prokon is one great way to get answers quick if you don’t want to sweat the small stuff.Īnd just in case you’re wondering whether Prokon is a sponsor of this site or post, then you’re wrong. It’s still relevant as fact because even software just like Prokon follows this algorithm. And no, you’re design won’t fail if you don’t. So if you’re still not following the latest soil analogy, you should be fine.
In fact, it’s still a staple in universities and even state licensure exams. computing the moment of inertia, the all too familiar combination of P/A and My/I, etc) won’t go away that quick.
Anyone here who uses Prokon’s column base design module? The one that deals with good old conventional isolated pad footings design?ĭespite the new pad-to-soil interaction analogous to strength design of concrete (see Joseph Bowle’s Foundation Analysis and Design), the traditional way of computing isolated pad footings (e.g.