Abunassar N, Alas M. Optimization of strength and durability properties of rubberized concrete mixtures containing silica fume using Taguchi method. Construction and Building Materials. 2025 Mar 21;468:140455.

This study investigates how rubberized concrete mixtures can be optimized by using silica fume and the Taguchi method to enhance both mechanical strength and durability. The work focuses on addressing the limitations often seen when using recycled rubber aggregate (RRA) in concrete — such as reduced compressive strength and increased porosity.

Nine concrete mixtures were designed with varying amounts of RRA, silica fume, and water-to-cement ratios. These mixes were tested for properties such as workability, dry unit weight, compressive and flexural strength, water absorption, and resistance to chemical exposure (including sulfuric and hydrochloric acid). The Taguchi method was used to identify the optimal mix combinations by analyzing the influence of each factor on the performance outcomes.

The results indicate that silica fume plays an important role in compensating for strength loss due to rubber inclusion, while also improving durability, especially under chemical attack. One of the mixes, containing 10% silica fume and 10% RRA, demonstrated balanced strength and durability, making it a suitable candidate for sustainable construction applications.

By combining recycled materials with a systematic optimization approach, the study contributes to efforts in reducing environmental waste while maintaining concrete performance. It shows the potential of well-designed rubberized mixtures as part of modern, sustainability-oriented engineering practices.

About the researcher

Assoc. Prof. Dr. Mustafa Alas is a faculty member in the Department of Civil Engineering at Near East University. His research interests include pavement engineering, asphalt binders and mixtures, machine learning, and sustainable construction materials. He is open to academic collaboration and can be reached via mustafa.alas@neu.edu.tr. 

Abstract
The present study aims to optimize the mixture design of rubberized concrete using the Taguchi method to enhance various performance parameters, including workability, compressive and flexural strengths, dry unit weight, water absorption, and resistance to sulfate and HCl acid exposure. Three primary control factors were investigated including silica fume, fine rubber, and coarse rubber. Each factor was evaluated at four substitution levels: 5 %, 10 %, 15 % and 20 % silica fume; 2.5 %, 5 %, 7.5 % and 10 % fine rubber; and 2.5 %, 5 %, 7.5 % and 10 % coarse rubber. A total of 16 mixtures were prepared and evaluated. The experimental results demonstrate the effects of these factors on concrete characteristics, with a focus on identifying optimal proportions that achieve enhanced mechanical strength and durability characteristics. Additionally, to maximize compressive strength, flexural strength, and resistance to sulfate and HCl attacks; the application of the Taguchi method proposed an optimized mixture design comprising 15 % silica fume, 2.5 % fine rubber and 2.5 % coarse rubber. The optimized mixture showed improvements in 28-day compressive strength, 56-day compressive strength, 28-day flexural strength, resistance to Na2SO4 and resistance to HCl of 4.55 %, 4.92 %, 5.34 %, 5.22 %, and 5.96 %, respectively.

For further details, access the original paper from the publisher’s link: Optimization of strength and durability properties of rubberized concrete mixtures containing silica fume using Taguchi method