For the subsequent iteration (*i* + 1), the cross-sectional area of the *j*th truss element (*A*_{i}_{+1,}_{j}) was adjusted based on the value of *ϕ*_{i}_{,}_{j} (Eq. (6)). The thickness of the *j*th shell element (*T*_{i}_{+1,}_{j}) was modified using Eq. (7). The target strain, *ε*_{t}, was given a value of 1250 *με*, corresponding to the middle of the lazy zone
Display Formula

(6)$Ai+1,j={Ai,j|\epsilon i,j|max\epsilon t,if\u2009\varphi i,j=1Ai,j,if\u2009\varphi i,j\u22601$

Display Formula(7)$Ti+1,j={Ti,j2(1+|\epsilon i,j|max\epsilon t),if\u2009\varphi i,j=1Ti,j,if\u2009\varphi i,j\u22601$