Is anyone familiar with H. M. Westergaard's Solutions for slabs-on-grade? "Ordinary" vs "special" theory of elasticity for slabs.

His solutions are used to determine the maximum deflections and critical stresses in a slab resting on a Winkler soil subject to a point load. His work, although considered simplified, is the basis for a lot of the contemporary SOG design.

In his pioneering 1926 paper (I can't find a public access pdf version), he briefly introduces two types of elastic theory for slabs. He provides an analogy by using beams:

1. "Ordinary Theory": Assumes that plane and perpendicular sections remain plane and perpendicular during bending. For beams, I imagine this just means Euler-Bernoulli beam theory.
2. "Special Theory": Abandons plan cross-section theory and tries to account for deformations due to the vertical stresses. For beams, this kind of sounds like Timoshenko beam theory, except that in Timoshenko theory we continue to assume plane sections remain plane, but not necessarily perpendicular (I think this is correct.)

He never really talks about what the equivalent is in terms of slab theory. At any rate, he goes on to say that you can find an equivalent area of distribution for a load where the stresses calculated using either theory matches up. Fine.

My (extremely limited) knowledge and understanding of plate theory makes me think of the following for slabs:

1. "Ordinary Theory": Classical plate theory (Kirchhoff-Love), where plane sections normal to the mid-surface (neutral axis?) remain plane and normal.
2. "Special Theory": First-order shear plate theory (Uflyand-Mindlin), where plane sections remain plane, but not necessarily perpendicular.

For the information I've provided, does my explanation seem fair for what we know today? I'm noting that Ulfyand-Mindlin theory or Mindlin-Reissner theory for slabs appear to have been proposed after 1926 which provides reason Westergaard arbitrarily calls it a "special theory".

Thanks!