Analysis of static stiffness properties of column-architrave structures of ancient buildings under long term load-natural aging coupling

Abstract

The column-architrave structures were widely used in the Yingxian wooden pagoda and pagoda has been in service for many years. Over time, it has been subjected to stress and the effects of natural aging. In order to analysis the ability of the structures to resist deformation under specific static excitation, a study of the static stiffness properties of column-architrave structures in ancient buildings considering long term load-natural aging coupling was carried out. Based on the Gerhards model, a strength degradation model has been developed for column elements and architrave elements, taking into account long-term loading and natural aging effects; By constructing a regular model and a realistic model, the deformation of the regular model under long term self weight load and the deformation of the realistic model under long term self weight load and aging are simulated by finite element model; The relationship between deformation values and static stiffness as a function of time is investigated through multiple points of the column-architrave structures, and the reliability of the proposed model is verified by extracting and comparing data from the automated real-time 3D monitoring system of the wooden pagoda. The results show that the numerical simulations of both models show that the middle of the architrave is more easily deformed than the mortise and tenon joint structures; The deformation resistance of the realistic model is lower than the deformation resistance of the regular model, and the natural aging effect has a non-negligible deterioration effect on the deformation of the column-architrave structures; For the column and architrave elements, they are likely to become unstable at 3330 AD and 3543 AD respectively, which means that after 1307 and 1520 years, the static stiffness of both elements tends to decrease with time in service, with the decrease in static stiffness of the architrave elements being less than that of the column elements.