Al-Naghi Ahmed A Alawi, Ali Tariq, Inam Inamullah, Qureshi Muhammad Zeeshan, Kahla Nabil Ben, Ghazouani Nejib, Ahmed Hawreen
Civil Engineering Department, University of Ha'il, 55476, Ha'il, Kingdom of Saudi Arabia.
Department of Civil Engineering, Swedish College of Engineering and Technology, Wah, 47080, Pakistan.
Sci Rep. 2025 Jul 8;15(1):24542. doi: 10.1038/s41598-025-02234-1.
As concrete production accounts for a large percentage of worldwide CO emissions, there is a need for alternative sustainable construction materials. Simultaneously, the increasing generation of construction and demolition waste has led to the growing interest in using recycled aggregates (RA) in concrete. However, recycling aggregate (RAC) tends to demonstrate poor mechanical and durability performance because of relatively high porosity and weak interfacial transition zone existing in RA. This study explores the synergistic effects of coconut fiber (CF), wheat straw ash (WSA) and silica fume (SF) in its enhancement of RAC performance. Mechanical (compressive and tensile strengths) and durability (water absorption and acid resistance) characteristics of RA (50%, 75%, and 100%) incorporated with various proportions of WSA (5%, 10%, and 15%) have been studied. Additionally, CF (1.5%) and SF (7%) were also added in all mixtures. The findings show that the optimum mix (10% WSA and 50% RA) achieves a compressive strength of 30.7 MPa at 90 days. The tensile strength was also improved, with the 10% WSA mix offering the highest tensile strength of 3.89 MPa at 90 days. Durability tests showed that water absorption decreased, and acid resistance improved with the addition of WSA, especially with 10% WSA, which had the lowest water absorption of 4.8%. Microstructural Analysis of the concrete matrix showed, particularly for mixes with increased WSA content, indicate lower porosity and better bonding. The present work establishes base evidence for the use of CF, WSA and SF in improving the performance and sustainability of RAC and is a viable option for construction applications, particularly in the presence of the high construction and demolition waste regions.
由于混凝土生产在全球二氧化碳排放中占比很大，因此需要替代的可持续建筑材料。同时，建筑和拆除废物的产生量不断增加，这使得人们对在混凝土中使用再生骨料（RA）的兴趣日益浓厚。然而，由于再生骨料中存在较高的孔隙率和薄弱的界面过渡区，再生骨料混凝土（RAC）往往表现出较差的力学性能和耐久性。本研究探讨了椰纤维（CF）、麦秸灰（WSA）和硅灰（SF）对提高RAC性能的协同作用。研究了掺入不同比例WSA（5%、10%和15%）的RA（50%、75%和100%）的力学性能（抗压强度和抗拉强度）和耐久性（吸水率和耐酸性）特征。此外，所有混合料中还添加了CF（1.5%）和SF（7%）。研究结果表明，最佳配合比（10%WSA和50%RA）在90天时的抗压强度达到30.7MPa。抗拉强度也有所提高，10%WSA混合料在90天时的抗拉强度最高，为3.89MPa。耐久性试验表明，加入WSA后吸水率降低，耐酸性提高，尤其是10%WSA时，吸水率最低，为4.8%。混凝土基体的微观结构分析表明，特别是对于WSA含量增加的混合料，孔隙率较低，粘结性较好。本研究为使用CF、WSA和SF改善RAC的性能和可持续性提供了基础证据，是建筑应用的一个可行选择，特别是在建筑和拆除废物量大的地区。
