Prediction and Optimization of Poisson’s Ratio of Sawdust Ash Geopolymer Concrete

Abstract

Introduction: Geopolymer concrete is a more environmentally friendly option than traditional cement because it reduces greenhouse gas emissions during production. It is composed of an alkaline solution with sodium or potassium silicate and sodium or potassium hydroxide, as well as a source material rich in silica and alumina.

Objectives: The primary focus of the study was to predict maximize the Poisson’s ratio of the concrete, particularly when incorporating sawdust ash as the source material.

Methods: In this investigation, thirty geopolymer concrete samples were created in the laboratory using a mix design approach based on Scheffe’s (5,2) model.

Results: The research developed a mathematical model for prediction and also identified the optimal Poisson’s ratio of geopolymer concrete incorporating sawdust ash to be 0.2695, as well as specific concentration ratios of NaOH, Na2SiO4 to NaOH, sawdust ash in the binder, water to binder, and activator to sawdust ash at 141937, 2.8272, 43.8481, 0.0885, and 2.9876 respectively. Additionally, MATLAB-based computer programs were used to optimize and predict the ideal mixture proportions for sawdust ash-based geopolymer concrete.

Conclusion: The results revealed that subjecting sawdust ash to pyrolysis in the absence of oxygen significantly affects its pozzolanic properties and, consequently, the characteristics of the concrete. Models for prediction and optimization of the Poisson’s ratio of sawdust ash geopolymer concrete were developed alongside a MATLAB code.