Dynamic characteristics changes of masonry arches exposed to elevated temperature

In this study, the changes in the dynamic characteristics of masonry arches exposed to elevated temperatures were investigated experimentally and numerically. Firstly, the material properties were analyzed at different temperatures, ranging from 200(degrees)C to 800(degrees)C, through experimental tests. The constructed arch specimens were then subjected to heat to investigate the effects of elevated temperatures on their dynamic characteristics. Ambient vibration tests were performed before and after heating to identify natural frequencies and mode shapes. Furthermore, numerical models of the arches were developed, and a model updating procedure was implemented to minimize the differences between the numerical and experimental data. The findings indicated that elevated temperatures led to notable decreases in the compressive strengths of both the stone and the mortar. This decrease significantly degraded the stiffness of the masonry arch samples, consequently having a profound effect on their dynamic properties.