Vitruvian binders in Venice: First evidence of Phlegraean pozzolans in an underwater Roman construction in the Venice Lagoon
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View abstract on PubMed
Summary
This summary is machine-generated.Roman mortars from a Venetian well-cistern used Phlegraean Fields volcanic pozzolans, demonstrating advanced ancient engineering. Underwater conditions promoted pozzolanic reactions, enhancing mortar properties.
Area Of Science
- Archaeometry
- Materials Science
- Geochemistry
Background
- Roman mortars from a 1st c. CE well-cistern in the Venice Lagoon were analyzed.
- The mortars contained lime binder, local ceramic fragments, sand, and imported pyroclastic aggregates.
Purpose Of The Study
- To identify the origin of pyroclastic aggregates used in Roman mortars.
- To understand the reaction mechanisms of these mortars in an underwater environment.
Main Methods
- Polarized Light Optical Microscopy (PLM), Quantitative Phase Analysis-X-Ray Powder Diffraction (QPA-XRPD), and Scanning Electron Microscopy with Energy-Dispersive X-Ray Spectroscopy (SEM-EDS).
- Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) for geochemical analysis of volcanic clasts.
- Comparison of geochemical fingerprints with Italian Plio-Quaternary magmatic districts.
Main Results
- Mortars identified as lime-based with local aggregates and natural pozzolans.
- Geochemical analysis indicated the pyroclastic aggregates originated from the Phlegraean Fields volcanic district.
- Significant pozzolanic reactions observed, forming M-A-S-H hydrates, especially in finer volcanic particles and shards.
- Minimal carbonation of lime binder observed in the underwater environment.
Conclusions
- The study confirms the use of Phlegraean pozzolans in Roman mortars, aligning with Vitruvius' recommendations.
- Underwater conditions in the Venice Lagoon promoted pozzolanic and para-pozzolanic reactions, enhancing mortar durability.
- Ancient Roman engineers possessed advanced knowledge of material selection and application for marine environments.
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