The Mechanical Performance of a Liao Dynasty Five-Step Outer Eave Column-Head Dougong Bracket: A Numerical Investigation

Abstract

The Dougong bracket is a critical seismic-resistant element in traditional Chinese timber structures, yet its complex mechanical behavior requires further investigation. This study numerically evaluated the static structural performance of a Liao Dynasty ‘Five-Step Outer Eave Column-Head Dougong Bracket’ from the Dule Temple Gate using finite element analysis. An orthotropic constitutive model calibrated with Pinus sylvestris test data and the Hill yield criterion were implemented in ANSYS. Simulations under vertical monotonic and horizontal low-cycle reversed loads assessed strength, deformation, and energy dissipation. Key findings include a maximum vertical load-bearing capacity of 344 kN, with stress concentrations up to 27.4 MPa at the Huagong-Ludou interface. Horizontal loading revealed symmetrical hysteresis loops, peak loads of 999 kN (Y-axis) and 522 kN (X-axis), ductility coefficients of 2.45 to 3.63, and equivalent viscous damping values of 0.097 to 0.122. The vertical response exhibited tri-linear stiffness degradation, while horizontal behavior followed multi-linear restoring force models. These results validate FEA as an efficient tool for assessing Dougong brackets, supporting the conservation and understanding of historical timber structures.