A scale model with bricks printed in 3D has been designed within the framework of an H2020 European project, making it possible to study the patterns of cracking and damage in the structure from the beginning of the earthquake.
Professor of the University of Alicante (UA) Department of Civil Engineering Salvador Ivorra is part of the European project ‘SEeismic BEhavior of Scaled MOdels of groin VAults made by 3D printers’ (SEBESMOVA3D) whose goal is to learn the resistance mechanism of groin vaults in the event of an earthquake. The vaults represent a very common typology of structural elements of roofs in monumental buildings and, in particular, in historic masonry churches.
According to the UA researcher, once this mechanism is known, patterns of reinforcement can be suggested in order to increase resistance to seismic movements, given that this type of structure is very sensitive to earthquakes, as could be seen in the Lorca earthquake and other more recent ones that have occurred in Italy. L´Aquila, Amatrice, etc.”
In addition to the UA, the consortium, coordinated by the Polytechnic University of Bari, has been composed by experts from the universities of Edinburgh, Bolonia and Bristol since 2017. More than 60 experimental seismic experiments have been tested with printed-brick groin vaults using 3D printers to generate the scale geometry of the bricks and, subsequently filled with mortar to simulate a 2.5 x 2.5 metre-to-scale real vault, Ivorra stated. The tests have been carried out under different support conditions: fixed restrictions, or springs at the base simulating the rigidity of typical columns or load-bearing walls in order to analyse their behaviour under seismic actions.
To this end, the European consortium has obtained a type of “lego blocks» that allows the tests to be carried out, even until the collapse, and thus to see the patterns of fissure and damage from the beginning. Each brick has sensors to know exactly where it is during the earthquake and to analyse which blocks are affected the most or least, the UA expained.
Also, researchers have made recordings with high-speed cameras to see exactly where crevices start, their progress and which ones lead to the collapse. According to Salvador Ivorra, one of the advantages of this procedure is the possibility of repeating the tests many times with different earthquakes because the bricks can be reused and the scale model can be easily rebuilt.