Title:
An Overview of Heat Signature Technology and its Application to Proposed Concrete In-place Thermal Cracking Field Curing Indices
Author(s):
F.F. Radjy
Publication:
Symposium Paper
Volume:
241
Issue:
Appears on pages(s):
111-132
Keywords:
adiabatic; calorimetry; cracking; fast-track; heat signature; hydration; simulation; thermal.
DOI:
10.14359/18654
Date:
4/1/2007
Abstract:
Heat of hydration and its rate play key roles in concrete thermal cracking and high-early strength development for fast track construction. Heat properties are also unique indicators of both the quality and the performance of cement, cementitious materials, and chemicals in concrete. Heat Signature is an automated method of measuring concrete heat of hydration and its rate, and adiabatic temperature rise and its rate versus concrete maturity (equivalent curing age at 68 °F). The measurements are performed on full size concrete specimens via the Internet/Intranet, and together with mixture information are saved to a database. Heat signature data in combination with simulation enable projecting concrete field performance in terms of its temperature, maturity, and strength profiles as a function of job site weather conditions and placement and curing plans. The paper reviews the underlying heat signature theory, its history, and reviews and interprets typical data from the many measurements in the US. To better index a given mix design’s field performance, a consistent set of thermal cracking and high-early curing age indices are introduced.