Development law of axial compression and cracks in ancient brick masonry

Abstract

Abstract To study the axial compressive strength of an ancient brick masonry and the occurrence and development of cracks, compressive tests were carried out on two groups of ancient brick masonries prepared using different mortars. The load–deformation curve, stress–strain curve, and crack data of the masonry were obtained. Based on the method used to determine masonry cracking, the cracking load was comprehensively evaluated by analyzing the stress process of the masonry, load–deformation curve, single-crack length, and crack development. The stress–strain relationship of the masonry was established, and a trilinear model was fitted, to accurately reflect the relationship between the crack length and the load. Unlike modern masonries, the cracks in ancient brick masonries onset early and develop rapidly. The cracking load was concentrated in the range of 0.30 f m –0.45 f m , where fm is the compressive strength. At 0.70 f m , through cracks were formed, and at 0.81 f m , the specimen entered the failure stage. The damage state of the masonry was evaluated by calculating the crack density, and the final crack density was found to be 7.85\xa0m/m2. This study provides an experimental and theoretical basis for the evaluation and protection of ancient buildings.