Mortar-diatom composites for smart sensors and buildings

Abstract

© 2021 Optical Society of America under the terms of the OSA Open Access Publishing Agreement To address the challenge of appropriate cementitious materials that can support future optical fbre sensors with reduced strains for smart city infrastructure, reducing structural heterogeneity by integrating diatomous earth is proposed. A series of samples made up of commercial grade instant mortar and an increased percentage of diatomous earth are fabricated and characterised. Mindful of the growing importance of “in-the-feld” measurements and diagnostics to wider construction technology evolution, hardness properties are measured using Mohs scratch test and portable feld durometers; the latter was shown to be efective in post-plasticity assessment of these cement composites. Within experimental error low added concentrations improve cement hardness whilst making the cement more plastic. Structural colour is introduced by the diatoms and novel characterisation using a smartphone and polymer lens proposed and demonstrated. The implications for CO2 trapping and intelligent structural health monitoring (ISHM) for internet-of-things (IoT) in smart city infrastructure are discussed.