Characterisation of Roman Mortar from the Archaeological Site of Mirobriga

Author(s): Alvin Sern Hao Chua, Cristina Galacho, Patrícia Moita, José Carlos Quaresma
Paper category: Proceedings
Book title: Proceedings of the 5th Historic Mortars Conference
Editor(s): José Ignacio Álvarez, José María Fernández, Íñigo Navarro, Adrián Durán, Rafael Sirera
ISBN: 978-2-35158-221-3
e-ISBN: 978-2-35158-222-0
Publisher: RILEM Publications SARL
Publication year: 2019
Pages: 727-742
Total Pages: 16
Language : English

Abstract: Mirobriga is a Roman site located in the municipality of Santiago do Cacém, in Setúbal, a
district in the southwest of Portugal. Mortar samples were collected from the domestic,
commercial buildings, and public buildings from the site. The samples may be divided
according to their function – filling, rendering, and plaster. The chemical, mineralogical, and
microstructural characterisation of the samples was performed using a number of
complementary techniques – stereomicroscopy, polarised light microscopy, chemical and
granulometric analysis, thermogravimetric analysis (TGA), powder X-ray diffraction (XRD),
and variable pressure scanning electron microscopy-energy dispersive spectrometry (SEM-
EDS). The results show that in most of the samples, the aggregates consist of quartz sand,
whilst the binder is lime-based. The exception, however, may be seen in the samples where
stratigraphy is present. In such samples, the external layer of the mortar functions as a
plaster, and both the aggregate and the binder consist of calcite. In addition, the majority of
samples have a binder to aggregate ratio of 1 : 3. As a whole, the raw materials used for the
production of the mortars may be said to be quite similar, and shows little difference
between the filling and rendering mortars, though the aggregates of these two types of
mortar are different from those functioning as plaster.
Keywords: Mirobriga, Roman mortars, SEM-EDS, XRD, TGA.

Online publication : 2019
Publication type : full_text
Public price (Euros) : 0.00