Evaluating Applications of Field Spectroscopy Devices to Fingerprint Commonly Used Construction Materials

Abstract

This report documents the results of the evaluation of practical portable spectroscopic equipment for in-situ analysis of a wide range of commonly used construction materials. The initial range of spectroscopic techniques evaluated by the project Team included Fourier-Transform Infrared (FT-IR) Spectroscopy, Size-Exclusion Chromatography (SEC), Nuclear Magnetic Resonance (NMR), X-Ray Fluorescence (XRF), and X-Ray Diffraction (XRD). The aforementioned techniques were applied to the following construction material categories: epoxy coating and adhesives, traffic paints, Portland cement concrete with chemical admixtures and curing membranes, asphalt binders, emulsions, and mixes with polymer additives. A series of laboratory and in-situ tests showed that the compact FT-IR spectrometer in the Attenuated Total Reflectance (ATR) mode, hand-held XRF instrument, and RTA’s Raman analyzer were successful in fingerprinting epoxy coatings and adhesives, curing compounds, and waterborne traffic paints. The ATR method also positively identified chemical admixtures in fresh mix samples and verified polymer presence in asphalt binders and emulsions. An electronic library of signature spectra of the materials tested in this project was created and submitted to SHRP 2 administration. Among other deliverables of this project are proposed AASHTO standards of practice for the analysis of titanium content in traffic paints by XRF, and identification of chemical admixtures by ATR.