Simulation Study on the Static Characteristics of ‘Five-tier Outer Eave Column-head Dougong Bracket’ from Yanghe Tower in Yuan Dynasty

Abstract

Finite element analysis (FEA) was used to investigate the static structural behavior of the ‘Five-tier Outer Eave Column-head Dougong bracket’ of the Yanghe Tower from the Yuan Dynasty. Based on GB/T standard testing results for the mechanical properties of Pinus sylvestris, an improved ANSYS orthotropic anisotropic model was established. The Hill yield criterion was applied to characterise the wood’s plasticity. The model was calibrated against experimental results in the literature. Through simulations of vertical monotonic loading (Z-axis) and horizontal low-cycle cyclic loading (Y-axis and X-axis), the structure's strength, deformation, and energy dissipation capacity were analysed. Results indicate that the maximum vertical bearing capacity at the interface between the Huagong-rear-end/Sandou interface reached 343 kN, with peak stress reaching 16.9 MPa. Horizontal loading produced symmetric hysteretic curves, with maximum horizontal thrusts of 737 kN (Y-axis) and 523 kN (X-axis). The ductility coefficients were 2.59 and 3.59 respectively, while equivalent viscous damping coefficients were 0.072 and 0.144. Vertical response conformed to a trilinear stiffness degradation model, whilst horizontal response followed a multilinear restoring force model. It was found that finite element analysis (FEA) provided an economical and reliable method for evaluating the mechanical performance of Dougong, offering significant reference value for the conservation of timber heritage structures.