A method for determining contact parameters in discrete element modeling: application to masonry pagodas

The discrete element method (DEM) is an effective approach for simulating seismic cracking and damage processes in ancient masonry pagodas. Accurate representation of masonry behavior and dynamic fracture characteristics requires a reasonable determination of contact parameters between block elements. To address this, a contact parameter selection method for the model based on the physical properties of materials ( α _p method) is proposed, incorporating mechanical property tests of masonry under different stress states and referring to the shaking table test results of the Xuanzang Pagoda model in China. It is applied to analyze block interface shear displacements, displacement time histories at monitoring points, and peak displacements of the pagoda model under different seismic conditions. The numerical results are compared with both the elastic theory-based method ( α _e method) and experimental measurements. Findings indicate that the α _p method provides a more reasonable simulation of the dynamic effects of the pagoda model and the dynamic transmission behavior of the internal infill. Under strong seismic excitation, the error between the predicted dynamic response of the pagoda and the shaking table test results is only 16.3%, which is reduced by 50% compared with the α _e method. This approach more effectively captures material deformation and the typical characteristics of seismic damage evolution in pagodas. This research offers a useful reference for discrete element simulations of failure modes and seismic mechanisms in historic masonry structures.