A multidisciplinary approach involving chemical, petrographic, and physical characterization techniques will be applied to the characterization of ACMs. The tasks aim to develop a protocol for systematically and expeditiously evaluating mixtures containing ACMs (for example, CeraTech and Solidia cements). The principal objectives are to evaluate their structural and durability performance and to identify properties and test methods that will assure their quality and performance for highway applications. To achieve the objective of this study, the research team envisions the following steps: Evaluation of rheology, setting, mechanical properties, volume change, transport properties and durability using traditional and new emerging test methodsChemical analysis of the mixtures, which entails x-ray florescence, x-ray diffraction, scanning electron microscopy, and Thermogravimetric analysis.Petrographic analysis, which includes microscopic examination and analysis of the constituents of hardened cementitious materials. Alternative Cementitious Materials (ACMs*) are materials that have little or no portland cement.
The key project objectives are:
- Characterization of performance of concrete-making materials, which include analysis of mechanical, durability, chemical, and physical properties of concrete containing the constituents and their interactions.
- Analysis of the rheological and mechanical properties of fresh paste, mortar, and concrete, as required.
- Analysis of setting time, heat generation, and reaction mechanisms during hydration.
- Analysis of hardened concrete, mortar, and paste, including physically and chemically induced durability and strength issues.
The main focus of the study is to implement the concept of sustainability by evaluating and documenting the performance of concrete-making materials that are environmentally friendly, economical, and are socially acceptable. The ultimate goal is to reduce the carbon dioxide footprint associated with the production of cement while maintaining or improving the performance of concrete in the highway infrastructure.
Based on the limited data that have been acquired on the use of Solidia cement, it appears that its mechanical properties are equivalent or better than that of ordinary portland cement. Petrographic examination of the cores revealed that Solidia cement is primarily composed of glassy materials (perhaps slag) and crystalline materials (Wollastonite). X-ray diffraction and x-ray fluorescence examination of the constituents also confirmed presence of these materials.