Stone masonry is the construction technique used to build many of Europe’s built heritage: from large and impressive Roman amphitheatres to small and modest dwellings in European cities’ historic quarters. To protect these structures and preserve them for the future generations we need to understand the structural response of stone masonry under diverse loading conditions and to develop the tools for predicting it.
The EU-funded CRACK-IT project aimed at investigating and modelling the seismic response of irregular stone masonry, which is one of the most vulnerable construction typologies against earthquakes. The objectives of the project were: i) to obtain experimental evidence on the seismic response of stone masonry walls of various sizes, ii) to correlate damage due to an earthquake with residual mechanical properties and iii) to develop the numerical tools for the simulation of the structural response of stone masonry walls.
During the project, stone masonry walls of different dimensions were tested in the laboratory under in-plane horizontal actions simulating the loading and boundary conditions within a building during an earthquake. This experimental campaign tested the hypothesis whether walls of different size, due to the distribution of openings within a stone masonry building, have a different seismic response. The results of the experimental campaign provided valuable information on engineering properties (stiffness, force and displacement capacities) that are necessary for the seismic assessment of existing stone masonry structures and the design of new ones. Damage was correlated with the global residual capacity of damaged walls through the extraction of the crack skeletons and widths at different loading states. For the first time, geometrical digital twins of the tested walls were generated. This digital representation of the exact geometry and position of the stones within the wall’s volume allowed to correlate damage with the wall’s micro-structure and opened new possibilities for the validation of numerical modelling approaches for stone masonry structures.
The results of the project bring us one step further in developing the tools for the seismic assessment of irregular stone masonry structures and, hence, the protection of built heritage. Understanding the seismic behavior of stone masonry structures aids to the renewal of the interest for the use of stone masonry as a modern construction technique, contributing to the transition towards a sustainable and circular construction industry.
