Level: Intermediate
Philip J. Ramsey, Consultant and Professor, Predictum and University of New Hampshire
Christopher Gotwalt, JMP Director of Statistical Research and Development, JMP
Fly ash is common effluent of coal-fired power plants and is increasingly used as an admixture in concrete formulations. Although it takes 28 days for concrete to reach its full strength, the reaction temperature curves in the first 24 hours are indicative of long term strength. Using a mixture amount experiment with three admixture components and total amount of addition as a process variable, we analyze the 24-hour curing temperature data from each of 23 trials in the experiment. Historically only a feature of the temperature curves such as maximum temperature is analyzed directly; however, using the Functional Data Explorer we can analyze the full set of thermal curves from the experimental trials and subsequently use the Generalized Regression platform to find an optimum admixture composition and amount of addition for fly ash concrete. As far as we know this is a unique approach to the analysis of concrete formulation experiments and the FDE approach has wide applicability to many types of formulation and process experiments where traditionally only a single feature of each curve has been analyzed.