Non-invasive water content estimation in a tuff wall by DTS

Non-invasive water content estimation in a tuff wall by DTS

Agliata, R. (Università degli Studi della Campania “Luigi Vanvitelli”)
Bogaard, T.A. (TU Delft Water Resources)
Greco, Roberto (Università degli Studi della Campania “Luigi Vanvitelli”)
Minardo, Aldo (Università degli Studi della Campania “Luigi Vanvitelli”)
Mollo, Luigi (Università degli Studi della Campania “Luigi Vanvitelli”)
Steele-Dunne, S.C. (TU Delft Water Resources)

2019-02-10

Undesired presence of water in historical masonries has a negative effect on the walls and causes deterioration of decorative works covering the walls, such as frescoes and valuable plasters. To prevent this, non-invasive moisture measurements are needed that avoid damage during masonry inspection caused by sample taking or probe insertion. Active heated distributed temperature sensing (DTS) with optical fibres is widely used in hydrology to assess soil moisture content. The aim of this study is to examine the potential of this technique for non-invasive water content measurements in a real scale wall. The tested masonry is made of yellow Neapolitan tuff bricks, a material widely used in historical buildings of Campania (Southern Italy). Distributed temperature measurements are carried out with three different heating strategies (different power and duration) during the drying process following the complete saturation of the wall. The acquired temperature data are then processed with three different methods (estimators), so to identify the best combination of heating strategy and data processing approach. Despite the presence of a significant bias, it is possible to identify relationships between the gravimetric moisture content and the different estimators. Those relationships are influenced to a large degree by the thermal contact between the DTS cable and the masonry. This research shows it is possible to measure water content in tuff masonry using non-invasive active heated fibre optic cable when establishing good thermal contact between the cable and the masonry.

Building monitoring
DTS
Fibre optic
Moisture
Non-invasive measurement
Tuff masonry
Water content

http://resolver.tudelft.nl/uuid:3e5499a3-dc76-4736-970b-f591eec773b7

https://doi.org/10.1016/j.conbuildmat.2018.11.250

2019-06-13

0950-0618

Construction and Building Materials, 197, 821-829

Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.

Institutional Repository

journal article

© 2019 R. Agliata, T.A. Bogaard, Roberto Greco, Aldo Minardo, Luigi Mollo, S.C. Steele-Dunne