Title:
Design of Alkali-Activated Slag-Fly Ash Concrete Mixtures Using Machine Learning
Author(s):
C. Gunasekera, W. Lokuge, M. Keskic, N. Raj, D. W. Law, and S. Setunge
Publication:
Materials Journal
Volume:
117
Issue:
5
Appears on pages(s):
263-278
Keywords:
alkali-activated concrete; artificial neural networks; compressive strength; mixture design; multivariate adaptive regression spline model
DOI:
10.14359/51727019
Date:
9/1/2020
Abstract:
So far, alkali-activated concrete has primarily focused on the effect of source material properties and ratio of mixture proportions on the compressive strength development. A little research has focused on developing a standard mixture design procedure for alkali-activated
concrete for a range of compressive strength grades. This study developed a standard mixture design procedure for alkali-activated
slag-fly ash (low-calcium, Class F) blended concrete using two machine learning techniques: artificial neural networks (ANN) and multivariate adaptive regression spline (MARS). The algorithm for the predictive model for concrete mixture design was developed using MATLAB programming environment by considering the five key input parameters: water/solid ratio, alkaline activator/ binder ratio, Na-Silicate/NaOH ratio, fly ash/slag ratio, and NaOH molarity. The targeted compressive strengths ranging from 25 to 45 MPa (3.63 to 6.53 ksi) at 28 days were achieved with laboratory testing using the proposed machine learning mixture design procedure. Thus, this tool has the capability to provide a novel approach for the design of slag-fly ash blended alkali-activated concrete grades matching to the requirements of in-place field constructions.
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