underfire
You state:
The contact load portion you ref is not applicable to the OP. Contact loading assumes there are no spreaders, it is the direct contact point of the object. The OP specifically ref spreaders.
And:
You quote page 221, note the next page, 222. Contact load with spreaders and without. Note the surface area used with the spreaders.
But in the same post you have included a calculation for contact load, which includes spreaders:
Contact Load = (500 + 20 ) / 0.48 = 1084 kg/m squared.
If we apply exactly the same process to the OP we get
Contact Load = 2000 / 3 = 667 kg/m squared.