17 May 2024

Additive Regulated Concrete for Thermally Extreme Conditions

Abstract: This study details a multiprong effort to validate the Cold Regions Research and Engineering Laboratory’s solution for concrete construction and repair in cold weather, Additive Regulated Concrete for Thermally Extreme Conditions (ARCTEC). ARCTEC is the product of several years of research and consists of a testing and simulation workflow which generates scenario-sensitive guidance for use of accelerating admixtures in concrete. This report details efforts to validate ARCTEC using real-world, full-scale, field demonstrations. These demonstrations were used to collect data on the behavior of concrete obtained through conventional supply chains, to assess the accuracy of the simulation component of the workflow, and test efficacy of ARCTEC guidance in achieving frost protection. Results indicate that ARCTEC is at a high level of maturity, and provides additive dosage guidance that ensures frost protection and strength development in concrete placed where overnight lows fall as low as 0°F. The effort and cost required to implement ARCTEC as a cold weather protection strategy is minimal, and significantly less burdensome than conventional methods. Any cold region installation with a winter construction or repair needs and access to conventional concrete supply chains could field ARCTEC, and reduce the cost and schedule constraints associated with winter construction.

12 May 2021

Development of CORPS-STIF 1.0 with Application to Ultra-High Performance Concrete (UHPC)

Abstract: This report introduces the first release of CORPS-STIF (Concrete Observations Repository and Predictive Software – Structural and Thermodynamical Integrated Framework). CORPS-STIF is envisioned to be used as a tool to optimize material constituents and geometries of mass concrete placements specifically for ultra-high performance concretes (UHPCs). An observations repository (OR) containing results of 649 mechanical property tests and 10 thermodynamical tests were recorded to be used as inputs for current and future releases. A thermodynamical integrated framework (TIF) was developed where the heat transfer coefficient was a function of temperature and determined at each time step. A structural integrated framework (SIF) modeled strength development in cylinders that underwent isothermal curing. CORPS-STIF represents a step toward understanding and predicting strength gain of UHPC for full-scale structures and specifically in mass concrete.