## 3 Results  
### Effects of CWP on Concrete Workability  
Concrete workability refers to the ease of mixing, placing, and compacting without segregation or excessive bleeding [63]. This property significantly affects the quality and performance of hardened concrete. Numerous factors influence workability, with the water-binder ratio being the most critical. The type of cementitious material used also plays a vital role. Finer cementitious materials enhance workability while reducing bleeding and segregation [64]. Various Supplementary Materials have been employed to improve the workability of fresh concrete. For example, fly ash enhances workability, whereas materials like steel or synthetic fibres tend to reduce it [64]. The most common method for assessing concrete workability is the slump test. Table 3 provides an overview of the workability of the CWP concrete. The impact of CWP on concrete workability varies among studies. Generally, most findings indicate a decrease in slump as the CWP content increases. For instance, [PERSON] et al. [65] reported a reduction from 110 mm at 0% CWP to 95 mm at 30%, while [PERSON] et al. [28] recorded a sharper decline from 135 mm to 65 mm at 20% replacement. Li  
Figure 4: Analysis of 51 documents found on Scopus for KEY (ceramic AND wastes AND concrete AND powder AND cement). et al. [44] also noted a significant 52.4% slump loss at 20% CWP, attributing it to increased particle friction. Nevertheless, some studies have reported contrary results. [PERSON] et al. [66] observed a significant improvement in workability with finer CWP, and [PERSON] et al. [57] found an increased slump with bacterial additives. These inconsistencies likely stem from variations in the CWP particle size, additives, and admixtures. Finer particle sizes, such as those passing ASTM sieve #200 or ranging between 5 and 10 \(\upmu\)m, tend to increase water demand and reduce workability due to higher surface area and inter-particle friction [66]. Similarly, the angular and rough textures of the CWP particles intensify the internal friction within the mix, contributing to the slump loss. However, this effect can be moderated by the use of additives. For instance, superplasticisers like naphthalene-based Ceraplast-300 or sodium silicate (Na\({}_{2}\)SiO\({}_{3}\)) reduce water demand and improve dispersion, partially countering the stiffening effect of CWP [67]. Biological additives, like Bacillus megaterium, have also shown a positive effect on slump. [PERSON] et al. [65] tested the slump of concrete containing CWP at 0, 5, 10, 15, 20, 25 and 30%. The researchers revealed that as the proportion of CWP increased, there was a noticeable decrease in the workability of the concrete mixture. The researchers suggested that the workability of CWP concrete is enhanced only with superplasticisers. This agrees with the findings of [PERSON] et al. [28], who found that mixtures with CWP have a relatively lower slump than the reference mix without CWP. The addition of CWP to the cement decreased the concrete slump, as shown in Figure 5.  
[PERSON] et al. [67] investigated concrete containing CWP at 0-60% in steps of 10%. The study comprised the formulation of three distinct concrete mixtures: one without silicate (Na\({}_{2}\)SiO\({}_{3}\)), and two with 1% and 2% Na\({}_{2}\)SiO\({}_{3}\) of the binder. The researcher's findings showed that in Mix 1, the slump value decreased compared to that of conventional concrete. However, when 10% and 40% of CWP were used as a replacement, the slump value increased by 3.03% and 6.06%, respectively. In Mix 2, which contained 1% Na\({}_{2}\)SiO\({}_{3}\) in the binder, the slump value generally decreased, except at 10% and 40% CWP. The research  
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indicates that the addition of CWP can have varying effects on the workability of CWP concrete.