A FRCM technique for strengthening of masonry domes against near-fault pulse-like vertical excitations

Abstract

Masonry domes have been used extensively in historic architecture, covering large interior spaces in structures ranging from temples, mausoleums, palaces and fortresses to baths, churches, and mosques. This research is motivated by the post-earthquake observations following the 2023 Kahramanmaras, earthquakes, which revealed significant structural damage to masonry domes caused by near-fault pulse-like horizontal and vertical ground motions. Previous studies in the literature have not investigated the impact of near-fault pulse-like vertical and horizontal ground motions on the seismic performance of masonry domes. This paper aims to explore the impact of the vertical component on the seismic damage behavior of masonry domes subjected to near-fault pulse-like ground motions. Additionally, it seeks to propose a cost-effective seismic strengthening technique characterized by minimal intervention, improved workability, and reduced cost. A 3D finite element model of a masonry dome with a drum was created using the isotropic continuum macro modeling technique with homogenized properties. The Concrete Damage Plasticity (CDP) model was selected as the nonlinear material model. Near-fault pulse-like vertical and horizontal ground motions recorded during the February 6, 2023, Kahramanmaras, earthquake (M7.7) were chosen for the nonlinear analysis. Initially, displacements, tensile strains, and damage patterns of masonry domes subjected to near-fault pulse-like vertical and horizontal ground motions were obtained and thoroughly evaluated for V/H (the peak vertical ground acceleration to the peak horizontal ground acceleration ratio) ratios of 0.0, 0.50, 0.75, 1.0, and 1.25. Subsequently, seismic analyses were conducted on masonry domes strengthened with four different Fabric Reinforced Cementitious Mortar (FRCM) configurations under near-fault pulse-like excitations with a V/H ratio of 1.25 to propose an optimal strengthening technique.