The FHWA Mobile Concrete Technology Center (MCTC) is offering a one-page tech transfer document that provides some observations on a simple, inexpensive field testing concrete & cementitious material hydration. Hydration, of course, creates exothermic chemical reactions, which can be monitored by measuring the total heat generated over time.
“Monitoring Concrete Consistency using Semi-Adiabatic Calorimetry” descibes a test method that can monitor batch-to-batch consistency of concrete mixtures. The test works by casting a standard concrete cylinder, then placing it in the calorimenter, recording the time-temperature curve (or heat signature), then comparing the curves of other samples from the same mixture.
Calorimeters are described as effective tools during mix design to determine potential material incompatibility or optimal dosages/sequence of addition of admixtures. They can be used to determine setting times and saw cut times in lieu of physical testing. Semi-adiabatic calorimeters can also be used as a quality control tool to monitor variations in the sources, quantities, and chemistry of portland cement, supplementary cementitious materials, and chemical admixtures during concrete production. Click here to download a copy of the document.