Imagine a load hanging from a wire. The load is in equilibrium with the force in the wire. Think of the wire as made of two wires each of half the cross-sectional area of the original wire. Nothing changed. Half the load is taken by each wire. What happens if we reduce the modulus of the wires...
You are right to point out that the forces are all in equilibrium but when the wall becomes less stiff there is no longer strain compatibility. WALLAP uses an "initial stress" technique to compensate for the incompatibility. It does not start from scratch. BTW - although not mentioned in the...
