Statistical Modelling of the Mechanical Behaviour of Alkali Activated Concrete with Fibers
| International Journal of Civil Engineering |
| © 2025 by SSRG - IJCE Journal |
| Volume 12 Issue 11 |
| Year of Publication : 2025 |
| Authors : Ganta Mounika, Burugu Rahul Bharadwaj |
10.14445/23488352/IJCE-V12I11P108
How to Cite?
Ganta Mounika, Burugu Rahul Bharadwaj, "Statistical Modelling of the Mechanical Behaviour of Alkali Activated Concrete with Fibers," SSRG International Journal of Civil Engineering, vol. 12, no. 11, pp. 98-109, 2025. Crossref, https://doi.org/10.14445/23488352/IJCE-V12I11P108
Abstract:
This study develops quadratic nonlinear regression models capable of predicting the 28-day compressive and flexural robustness of Fiber-Reinforced Alkali-Activated Concrete (FRAAC) from critical input factors, which include slag content, alkaline solution to binder ratio, fiber content, fiber factor, fiber modulus, sodium silicate to sodium hydroxide ratio, and the activator molarity. A complete dataset of data is constructed from multiple studies in an experimental database, and the models produced excellent overall prediction capability with a coefficient of determination (R²) for compressive strength of 0.962 (RMSE = 4.72 MPa) and flexural strength of 0.945 (RMSE = 0.68 MPa). Each of the most important predictors, as well as their interactions, is statistically noteworthy, with p-values less than 0.05, which lends confidence to the models' validity. The models are validated with the use of validation plots, residual plots, Q–Q plots, and Variance Inflation Factor (VIF) analysis. The models are robust and applicable well beyond the dataset. The analysis highlights many important nonlinear interactions between critical mix parameters, pointing to the need for precise proportioning to achieve optimal mechanical behavior. The validated models provide an efficient, data-driven tool that reliably estimates strength properties with little or no experimental trials.
Keywords:
Alkali Activated Concrete, Fibers, RMSE, Flexural strength, Compressive strength.
References:
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[CrossRef] [Google Scholar] [Publisher Link]
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[CrossRef] [Google Scholar] [Publisher Link]
[3] Huixia Wu et al., “Reusing Waste Clay Brick Powder for Low-Carbon Cement Concrete and Alkali-Activated Concrete: A Critical Review,” Journal of Cleaner Production, vol. 449, 2024.
[CrossRef] [Google Scholar] [Publisher Link]
[4] Wenlin Tu, and Mingzhong Zhang, “Multiscale Microstructure and Micromechanical Properties of Alkali-Activated Concrete: A Critical Review,” Cement and Concrete Composites, vol. 152, 2024.
[CrossRef] [Google Scholar] [Publisher Link]
[5] Isabel Pol Segura et al., “A Review: Alkali-Activated Cement and Concrete Production Technologies Available in the Industry,” Heliyon, vol. 9, no. 5, pp. 1-24, 2023.
[CrossRef] [Google Scholar] [Publisher Link]
[6] Hadi Bahmani, and Davood Mostofinejad, “Microstructural Characterization of Alkali-Activated Concrete using Waste-Derived Activators from Industrial and Agricultural Sources: A Review,” Case Studies in Construction Materials, vol. 22, pp. 1-20, 2025.
[CrossRef] [Google Scholar] [Publisher Link]
[7] Kennedy C. Onyelowe et al., “Optimizing the Utilization of Metakaolin in Pre-Cured Geopolymer Concrete using Ensemble and Symbolic Regressions,” Scientific Reports, vol. 15, pp. 1-34, 2025.
[CrossRef] [Google Scholar] [Publisher Link]
[8] Mana Alyami et al., “Hybrid Metaheuristic Optimized Random Forest Models for Predicting Compressive Strength of Alkali Activated Concrete,” Journal of Natural Fibers, vol. 22, no. 1, pp. 1-32, 2025.
[CrossRef] [Google Scholar] [Publisher Link]
[9] Zixin He et al., “Optimization of Alkali-Activated Mortar Utilizing Municipal Solid Waste Incinerator Bottom Ash and Slag: A Multi-Objective Response Surface Method Approach,” Construction and Building Materials, vol. 458, pp. 1-18, 2025.
[CrossRef] [Google Scholar] [Publisher Link]
[10] Saif Saad Mansoor et al., “Sustainable Alkali-Activated Concrete Modified with Cement Kiln Dust and Fly Ash: An Ai-Based Study,” Innovative Infrastructure Solutions, vol. 10, 2025.
[CrossRef] [Google Scholar] [Publisher Link]
[11] Alaa M. Morsy et al., “Experimental Verification for Machine-Learning Approaches in Compressive Strength Prediction of Alkali-Activated Concrete,” Journal of Structural Design and Construction Practice, vol. 30, no. 1, 2025.
[CrossRef] [Google Scholar] [Publisher Link]
[12] Yingjie Li et al., “Fresh State and Strength Performance Evaluation of Slag-Based Alkali-Activated Concrete using Soft-Computing Methods,” Materials Today Communications, vol. 38, 2024.
[CrossRef] [Google Scholar] [Publisher Link]
[13] Mo Zhang et al., “Effect of Composition and Curing on Alkali Activated Fly Ash-Slag Binders: Machine Learning Prediction with a Random Forest-Genetic Algorithm Hybrid Model,” Construction and Building Materials, vol. 366, 2023.
[CrossRef] [Google Scholar] [Publisher Link]
[14] Torkan Shafighfard et al., “Machine-Learning Methods for Estimating Compressive Strength of High-Performance Alkali-Activated Concrete,” Engineering Applications of Artificial Intelligence, vol. 136, 2024.
[CrossRef] [Google Scholar] [Publisher Link]
[15] Jian Gao et al., “R-Squared (R2)–How Much Variation is Explained?,” Research Methods in Medicine & Health Sciences, vol. 5, no. 4, pp. 104-109, 2023.
[CrossRef] [Google Scholar] [Publisher Link]
[16] Meysam Alizamir et al., “An Interpretable XGBoost-SHAP Machine Learning Model for Reliable Prediction of Mechanical Properties in Waste Foundry Sand-Based Eco-Friendly Concrete,” Results in Engineering, vol. 25, pp. 1-29, 2025.
[CrossRef] [Google Scholar] [Publisher Link]
[17] Uzoma Ibe Iro et al., “Optimization of Cassava Peel Ash Concrete using Central Composite Design Method,” Scientific Reports, vol. 14, pp. 1-23, 2024.
[CrossRef] [Google Scholar] [Publisher Link]
[18] Felipe Guíñez et al., “Effect of Mix Dosage on Rubberized Concrete Mechanical Performance: A Multivariable Prediction Model towards Design Provisions,” Journal of Building Engineering, vol. 90, 2024.
[CrossRef] [Google Scholar] [Publisher Link]
[19] Hemn Unis Ahmed, Ahmed S. Mohammed, and Azad A. Mohammed, “Multivariable Models Including Artificial Neural Network and M5P-Tree to Forecast the Stress at the Failure of Alkali-Activated Concrete at Ambient Curing Condition and Various Mixture Proportions,” Neural Computing and Applications, vol. 34, pp. 17853-17876, 2022.
[CrossRef] [Google Scholar] [Publisher Link]
[20] Y.S.N. Kishore et al., “Statistical Analysis of Sustainable Geopolymer Concrete,” Materials Today: Proceedings, vol. 61, no. 2, pp. 212-223, 2022.
[CrossRef] [Google Scholar] [Publisher Link]
[21] David Conciatori et al., “Statistical Analysis of Concrete Transport Properties,” Materials and Structures, vol. 47, pp. 89-103, 2014.
[CrossRef] [Google Scholar] [Publisher Link]
[22] Huibert Jilles Bezemer, and Mladena Luković, “Early-Age and Long-Term Deformations in Reinforced Slag-Based Alkali Activated Concrete,” Construction and Building Materials, vol. 476, pp. 1-12, 2025.
[CrossRef] [Google Scholar] [Publisher Link]
[23] Biswajit Majhi, Rohit Ranjan, and Subhajit Mondal, “Multi Response Optimization of Recycled Aggregate Based Alkali-Activated Concrete using Taguchi-Grey Relational Analysis Method,” Construction and Building Materials, vol. 441, 2024.
[CrossRef] [Google Scholar] [Publisher Link]
[24] Osama A. Mohamed et al., “Effect of Activator Concentration on Setting Time, Workability and Compressive Strength of Sustainable Concrete with Alkali-Activated Slag Binder,” Materials Today: Proceedings, 2024.
[CrossRef] [Google Scholar] [Publisher Link]
[25] Husam Alsarhan, and Amin Al-Fakih, “Performance and Sustainability of Industrial By-Products-Based Alkali-Activated Concrete: A Review,” Multiscale and Multidisciplinary Modeling, Experiments and Design, vol. 8, 2025.
[CrossRef] [Google Scholar] [Publisher Link]
[26] Feng Wu et al., “Size Effect in the Mechanical Characteristics of Steel Fiber Reinforced Alkali-Activated Slag/Fly Ash-Based Concrete,” Construction and Building Materials, vol. 443, 2024.
[CrossRef] [Google Scholar] [Publisher Link]
[27] Amr Hassan et al., “Effect of Hybrid Polypropylene Fibers on Mechanical and Shrinkage Behavior of Alkali-Activated Slag Concrete,” Construction and Building Materials, vol. 411, 2024.
[CrossRef] [Google Scholar] [Publisher Link]
[28] Nailia Rakhimova, and Caijun Shi, “Upcycling of Concrete Wastes as Precursors in Alkali-Activated Materials: A Review,” Construction and Building Materials, vol. 436, 2024.
[CrossRef] [Google Scholar] [Publisher Link]
[29] Shashwati Soumya Pradhan et al., “Development of Sustainable Slag-Based Alkali-Activated Concrete Incorporating Fly Ash at Ambient Curing Conditions,” Energy, Ecology and Environment, vol. 9, pp. 563-577, 2024.
[CrossRef] [Google Scholar] [Publisher Link]
[30] Mugahed Amran et al., “Fiber-Reinforced Alkali-Activated Concrete: A Review,” Journal of Building Engineering, vol. 45, 2022.
[CrossRef] [Google Scholar] [Publisher Link]
[31] Laura Rossi, Ravi A. Patel, and Frank Dehn, “New Analytical Models to Predict the Mechanical Performance of Steel Fiber‐Reinforced Alkali‐Activated Concrete,” Structural Concrete, vol. 26, no. 1, pp. 236-247, 2025.
[CrossRef] [Google Scholar] [Publisher Link]
[32] Siyuan Zhang et al., “The Stress-Strain Behavior, Durability, and Equilibrium Analysis of Copper-Coated Steel Fibers Reinforced Alkali-Activated Concrete,” Construction and Building Materials, vol. 462, 2025.
[CrossRef] [Google Scholar] [Publisher Link]
[33] Pathi Janardhan, R. Venkata Krishnaiah, and K.V.B. Raju, “Experimental Study on the Performance of Strength and Sorptivity of Fiber Reinforced Alkali Activated Geopolymer Concrete,” Materials Today: Proceedings, 2024.
[CrossRef] [Google Scholar] [Publisher Link]
[34] Tejaswini G. Panse et al., “Predictive Performance of Nano-Alumina and Zeolite-Based High-Performance Nano-Engineered Concrete: Integrative Application of Quantum Computing and Machine Learning with Optimization Techniques,” Quantum Machine Intelligence, vol. 7, 2025.
[CrossRef] [Google Scholar] [Publisher Link]
[35] Ravinder Kampa, and S. Venkateswara Rao, “Influence of Fiber Reinforcement on the Strength and Durability of High Strength Geopolymer Concrete with Multi Component Precursors,” Engineering Research Express, vol. 7, pp. 1-16, 2025.
[CrossRef] [Google Scholar] [Publisher Link]
[36] Houcine Bentegri et al., “Assessment of Compressive Strength of Eco-Concrete Reinforced using Machine Learning Tools,” Scientific Reports, vol. 15, pp. 1-24, 2025.
[CrossRef] [Google Scholar] [Publisher Link]