Seismic Analysis of Three Persian Arches

Analysis of stability in arch structures is a well-known fact in the conservation of historical monuments, stabilizing efforts, and the design of vernacular and rural structures. Therefore, the authors of this paper are set to explore and compare the threshold values of the seismic stability of three Persian arches, i.e., tokhm-e morqi, morabbaʿ, and panj-o-haft-e-tond. This experimental research uses geometrical analysis and physical models to find the threshold values for the seismic stability of these arches. Analysis of the arches is performed for different thickness-to-span ratios within the “limit state analysis” framework, using “thrust line analysis” with parametric modeling which offers a rigorous and rapid investigation. The results are then compared with the behavior of physical models. The thrust line analysis results show that the seismic stability of these arches, compared to one another, increases by increasing the thickness-to-span ratio and decreasing their rises. The physical models verify these results but show lower threshold values for seismic stability of the arches. So, the effective thickness of the arches must be considered in the analysis. Besides answering a practical problem, this paper gives an insight into the structural behavior of arches.