فهرست نشریات علمی دسترسی آزاد ایران

By partially replacing cement with zeolite and microsilica, the properties of self-compacting concrete can be enhanced. The aim of this research is to achieve an optimal and economical mix design for self-compacting concrete using the combination of zeolite and microsilica pozzolans to obtain the best properties of fresh and hardened concrete. Considering the role of aggregate grading in concrete, which significantly affects workability, strength, and even the economics of the design, this study first optimizes the grading of existing aggregates and constructs concrete to determine the best combined ratios of aggregates for self-compacting concrete. Furthermore, to investigate the mechanical and rheological properties of the concrete, two pozzolans, microsilica and zeolite, were used with combined ratios ranging from 5% to 20% by weight of cement. The results showed that the simultaneous use of 10% zeolite and 10% microsilica increases the compressive and tensile strength of concrete at 28 days by 32% and 23%, respectively, compared to the control sample (without microsilica and zeolite). As the consumption of pozzolans increases, the workability of self-compacting concrete decreases, necessitating an increase in the amount of superplasticizer to maintain the required workability. The consumption of superplasticizer in this study increased by up to 75% compared to the control sample, indicating a significant reduction from previous studies as a result of optimizing the mix design.