Mineralogical characterization of historical cement-based mortars from Rupnik military fortification line

Author(s): Petra Štukovnik, Janez Peter Grom, Marjan Marinšek, Violeta Bokan Bosiljkov
Paper category: Proceedings
Book title: Proceedings of the 5th Historic Mortars Conference
Editor(s): José Ignacio Álvarez, José María Fernández, Íńigo 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: 565-575
Total Pages: 11
Language : English

Abstract: The paper presents the results of cement-based mortars characterization that were taken
from rendered layers of military bunkers in Rupnik Line. The Rupnik Line was conceived as
part of the fortified defence system protecting the newly formed Rapallo border between
the Kingdom of Italy and the Kingdom of Yugoslavia, established in 1920. The mortars are of
different compositions and were aimed at protecting the massive concrete walls and slabs of
the bunkers, as well as representing camouflage layer that enabled merging of the bunkers
with the environment. Results of petrographic examination and microstructural and
chemical analysis (SEM-EDS) of the samples confirmed that locally available carbonate sands
with angular grains were used as an aggregate in the mortar. As a binder, pure Portland
cement clinker or mixture of the cement and ground granulated blast furnace slag were
used. The selection of the aggregate and binder type in particular mortar was based on the
colour of the produced “artificial stone” that should be light grey (cement and dolomite
aggregate) or greenish (cement, slag and limestone aggregate). The samples with the
dolomite aggregate grains show the characteristic appearance of the ACR reaction,
dedolomitisation of the aggregate grains and secondary calcite formation, along with the
Mg-Al-Si phase formation.

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