Axial Compression Tests on Rubble Stone Masonry Reproducing Opus Incertum of Ancient Pompeii

Abstract

In order to investigate the mechanical behaviour of the typical ancient rubble stone masonry type at the archaeological Pompeii site, an experimental program was carried out on masonry panels realized with the aim of reproducing the ancient technique opus incertum. Three panels (1.20m x 1.20m x 0.45m) were realized by using original rock units from ruins emerged in the excavation works at Regio V at the site and pozzolanic lime-based mortar realized according to the traditional technique. The first phase of the experimental program involved the accurate reproduction of Pompeii-like masonry panels and the execution of sonic pulse velocity tests to be compared with those carried out on original structures at the site. Thus, three in-situ diagonal compression tests were carried out to derive masonry shear strength and relevant correlation with sonic velocities. The last phase of the experimental program focuses on laboratory axial compression tests on five specimens extracted from the three panels analyzed in the first phase and is herein described in detail. The results of axial compression tests on two of such specimens in terms of axial compression strength and elastic modulus as well as the analysis of the crack pattern and failure mode is herein presented and discussed.

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References

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