Iowa Department of Transportation
Iowa Highway Research Board
Kejin Wangkejinw@iastate.edu email >
PCC Engineer, CP Tech Center
About the research
In the United States (US), the annual cement consumption is about 94.4 million metric tons, equivalent to approximately 750 million metric tons of concrete production. To reduce the negative environmental impacts, recycled wastes (e.g., slag and fly ash) have been widely used as supplementary cementitious materials (SCMs). The Iowa Department of Transportation has also been using concrete mixes containing 20% or more SCMs (e.g., slag and fly ash) and blended cement, like Types IS, IP, and recently IL. According to American Coal Ash Association, about 13 million metric tons of coal fly ash is used annually in cement and concrete in US. However, much of the present power plant ashes still hasn’t been beneficially used, mainly because these ashes don’t meet the national and state material specifications, thus generating a great challenge for power plants, concrete producers, and users as well as our society.
This research will address the power plant ash problem and ways to convert the waste (i.e., hazardous ashes) into a sustainable, beneficial, high-valued raw material source that can be used extensively in concrete as an innovative technology.