Federal Highway Administration
Kejin Wangkejinw@iastate.edu email >
PCC Engineer, CP Tech Center
Vern Schaefervern@iastate.edu email >
Interim Director, CEER
About the research
This report summarizes the findings of Phase I of the research project. The project is a comprehensive study of how supplementary cementitious materials (SCMs), can be used to improve the performance of concrete mixtures. The initial stages of this project consider several sources of each type of supplementary cementitious material (fly ash, slag, and silica fume) so that the material variability issues can also be addressed. Several different sources of portland cement (PC) and blended cement are also used in the experimental program. The experimental matrix includes 110?115 different mixtures; hence, the project is being conducted in three different phases.
This report contains a brief literature study to summarize the state of the practice in ternary mixtures. The literature study includes the efforts by state departments of transportation (DOTs) that have utilized ternary mixtures in field work (for example, Ohio DOT, New York State DOT, Pennsylvania DOT, Iowa DOT) to discuss practical concerns about field applications.
The initial phase covered in this report is a study with a large scope to identify materials combinations that will likely perform adequately in Phases II and III. Phase I of the study consisted of a 24-month laboratory program that studied the influence of multiple combination and proportions of cement, slag, silica fume, and fly ash on specific performance properties of mortar specimens. Test results are presented in this report. Chemical admixtures (water reducers, air-entraining agents, and accelerators) were included in this phase of the study to compare the effects of ternary mixtures on setting time, water demand, and air content. Phase I results have created the architecture for predicting the performance of ternary systems based on the material properties of the total cementitious system.