Shear analogy stiffness adjustment for CLT plates

In serviceability limit state, one-dimensional approaches are commonly used to estimate the bending stiffness and vertical displacement of cross-laminated timber (CLT) panels, such as the shear analogy method combined with mechanics of materials equations. Despite their simplicity, these equations disregard the orthotropic nature of wood’s elastic properties and the actual dimensions of CLT panels (treated as beams), affecting displacement predictions. In this context, a parametric study was conducted in this paper using the finite element method. Then, symbolic regression was applied to propose a correction factor for adjusting the stiffness of CLT panels obtained using the shear analogy method. The symbolic regression model for the correction factor demonstrated high accuracy (R2 = 0.9834). Adjusting the shear analogy stiffness with the proposed correction factor reduced the maximum error from 18% to 2% compared to the original method and numerical results. The model retained its accuracy in additional simulations, with percentage errors ranging from 0 to 1%.