Experimental and numerical study of the effect of steel Tie-rods on load-bearing capacity of Persian brick arches

Abstract

Arches are a fundamental feature of traditional Persian architecture. In Iran, arched structures have been used for centuries to cover expansive areas. They are typically made of wooden or steel tension members, called “tie-rods”. Tie-rods are essential in controlling and restraining horizontal forces caused by external loads occurring in arches and vaults. The current experimental study aims to assess the effect of steel tie-rods and their connection to the piers on the load-bearing capacity of Persian brick arches with three common geometries (semicircular, ordinary-four-centered, and ordinary pointed) subjected to a static gravity load. After experimentally determining the mechanical properties of the materials, a numerical model for arches using a nonlinear material behavior approach and the Willam-Warnke failure criterion was developed in ANSYS finite element code. The experimental results were subsequently compared to the numerical results. The results indicated that the type of tie-rod-pier connection and the arch’s geometry could affect the load-bearing capacity of arch-shaped structures subjected to static gravity loads. Finally, the performance of tie-rod-pier connections for different geometries of Persian arches was evaluated, especially for ancient structure restoration projects, and recommendations regarding tie-rod connections in different geometries of Persian arches were offered.