Numerical and Experimental Investigation into the Effects of Geometric Pattern on the Load-Bearing Capacity of Persian Brick Masonry Arches

The maintenance and repair of historic masonry structures have always been of importance. The identification of behavior of such structures under different loading conditions requires detailed experimental and analytical research. This paper experimentally and numerically examines the behavior of scaled Persian brick arches with seven common geometric patterns, including semicircular, drop four-centered, ordinary four-centered, raised four-centered, drop pointed, ordinary pointed, and raised pointed, under gravitational loading, asymmetric pier settlement, pier rotation, temperature changes, and earthquake. First, experiments were carried out to extract material properties. Then, three of the seven geometric patterns were fabricated experimentally and subjected to gravitational loading. The experimental data would be employed to develop and validate a finite element (FE) model. Finally, the FE models of all geometric patterns were developed under the aforementioned loads and analyzed under the assumption of nonlinear material behavior. According to the results, the brick arches were highly sensitive to pier rotation and settlement due to their brittle and fragile materials, and would fail at low displacements. The semicircular arch failed under all seismic records, suggesting that semicircular arches are seismically vulnerable. The raised pointed arch revealed the highest sensitivity to the inward rotation of the two piers. As a result, the raised pointed pattern claimed higher priority for repair and retrofit schemes. Further, the study of the arches under temperature changes indicated that none of them was at a high thermal failure risk.