Some clarifications:

CAESAR operation:
1. CAESAR calculates pressure thrust as Effective ID squared * PI/4 * pressure.
2. CAESAR applies this load in both directions, axially.
3. (And while not touched upon it above) CAESAR does not calculate thermal expansion for expansion joints.
4. The stiffness values dictate how the two nodes are permitted to move and rotate with respect to each other.

Physics theory vs. physics application:
We have inconsistent terminology and competing ideas that do not make sense when mixed together, and I think we're pouring gasoline onto the fire.

Take your example. 32.8' x 19.7' @ 1.45 psi. Let's put it in orbit around the earth. Let's put a weightless blind on either end of it and pressure it up.

You're telling us that the expansion joint is exerting 135,000 lbs of force out of either end of it, just as a function of pressure, meaning 130 kips of tension in the fabric.

Without pressure, I could otherwise hang a 135,000 lb weight from one end of it (back on Earth) while in the vertical and it'll be the same exact thing.

And if we assume the material is 1/8" thick, for a total area of about 1.1 square inches, the stresses in the axial is some 120 ksi.

The ultimate tensile strength of titanium is 63 ksi.

This line of reasoning simply does not make sense.