title: Nondestructive Handheld Fourier Transform Infrared (FT-IR) Analysis of Spectroscopic Changes and Multivariate Modeling of Thermally Degraded Plain Portland Cement Concrete and its Slag and Fly Ash-Based Analogs.
abstract: Concrete is by far the world's most common construction material. Modern concrete is a mixture of industrial pozzolanic cement formulations and aggregate fillers. The former acts as the glue or binder in the final inorganic composite; however, when exposed to a fire the degree of concrete damage is often difficult to evaluate nondestructively. Fourier transform infrared (FT-IR) spectroscopy through techniques such as transmission, attenuated total reflectance, and diffuse reflectance have been rarely used to evaluate thermally damaged concrete. In this paper, we report on a study assessing the thermal damage of concrete via the use of a nondestructive handheld FT-IR with a diffuse reflectance sample interface. In situ measurements can be made on actual damaged areas, without the need for sample preparation. Separate multivariate models were developed to determine the equivalent maximal temperature endured for three common industrial concrete formulations. The concrete mixtures were successfully modeled displaying high predictive power as well as good specificity. This has potential uses in forensic investigation and remediation services particularly for fires in buildings.
authors.affiliation: Agilent Technologies UK Ltd, Edinburgh, UK.
authors.forename: Pik
authors.initials: P
authors.lastname: Leung Tang
authors.affiliation: General Department of Forensic Evidence and Criminology, Dubai Police GHQ, Dubai, UAE University of Dundee, Dundee, UK.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Alqassim
authors.affiliation: University of Dundee, Dundee, UK.
authors.forename: Niamh
authors.initials: N
authors.lastname: Nic Daéid
authors.affiliation: University of Strathclyde, Glasgow, UK.
authors.forename: Leonard
authors.initials: L
authors.lastname: Berlouis
authors.affiliation: Agilent Technologies, Danbury, CT, USA john_seelenbinder@agilent.com.
authors.forename: John
authors.initials: J
authors.lastname: Seelenbinder
keywords: PLS modeling; Portable FT-IR; Portland cement; blended concrete; diffuse reflectance; fly ash; forensic investigation; ground granulated blast-furnace slag, GGBS; heat treatment; multivariate analysis; nondestructive testing, NDT; thermal damage