# Marble and Glass Waste Powder in Cement Mortar
## 2 Materials and Methods
### Physical and Chemical Properties of OPC, GWP, and MWP  
Distinct differences in the color of OPC, GWP, and MWP were observed during the production process, as shown in Figure 2. OPC exhibits a dark gray color, whereas both MWP and GWP are white. The white coloration of MWP and GWP is attributed to the lower amount of Tetra Calcium Alumino-ferrite (C\({}_{4}\)AF) present in these powders ([PERSON] and [PERSON], 2016).  
\begin{table}
\begin{tabular}{c c c c} \hline
**No.** & **Property** & **Test Method** & **Result** \\ \hline
1. & Unit weight (kg/m\({}^{3}\)) & ASTM C29 ([PERSON] and [PERSON], 2016) & 1583.93 \\
2. & Silt content (\%) & ASTM C117 ([PERSON] and [PERSON], 2016) & 2.71 \\
3. & Fineness modules & ASTM C33 ([PERSON] and [PERSON], 2016) & 2.5 \\
4. & Specific gravity & ASTM C128 ([PERSON] and [PERSON], 2016) & 2.6 \\
5. & Absorption (\%) & ASTM C128 ([PERSON] and [PERSON], 2016) & 3.03 \\
6. & Moisture content (\%) & ASTM C566 ([PERSON] and [PERSON], 2016) & 2.01 \\ \hline \end{tabular}
\end{table}
Table 1: Physical properties of fine aggregate.  
The physical properties of OPC, GWP, and MWP are summarized in Table 2. Notably, the Brunauer-Emmett-Teller (BET) surface area test analysis revealed that GWP (485.15 m\({}^{2}\)/g) and MWP (439.47 m\({}^{2}\)/g) exhibit significantly larger surface areas compared to OPC (339.56 m\({}^{2}\)/g). This increased surface area contributes to enhanced strength development of mortar as hydration reactions progress. The fineness of cement, a critical parameter representing the specific surface area, is closely linked to the physical and mechanical properties of the hydrated cement, including strength, setting time, and rheology [25].  
The results of X-ray fluorescence (XRF) showed that the main component of GWP is silicon oxide (SiO\({}_{2}\)), with minor quantities of aluminum oxide (Al\({}_{2}\)O\({}_{3}\)) and iron oxide (Fe\({}_{2}\)O\({}_{3}\)), as presented in Table 2. According to ASTM C618 [26], GWP qualifies as a Class N natural pozzolans because the sum of SiO\({}_{2}\), Al\({}_{2}\)O\({}_{3}\), and Fe\({}_{2}\)O\({}_{3}\) exceeds 70% (73.04%), and the LOI is below 10% (0.58). In contrast, MWP does not meet the pozzolanic material requirements specified in ASTM C618 [26]. It is classified as a calcareous material due to its high calcium oxide (CaO) content (52.82%) and a LOI of 41.8%.  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline  & **Items** & **OPC** & **GWP** & **MWP** \\ \hline \multirow{2}{*}{Physical Properties} & Surface Area (m\({}^{2}\)/g) & 339.56 & 485.15 & 439.47 \\  & Specific Gravity (g/cm\({}^{3}\)) & 3.15 & 2.37 & 2.65 \\  & Color & Dark grey & White & White \\ \hline \multirow{2}{*}{Chemical Compositions} & CaO (\%) & 64.31 & 7.58 & 52.82 \\  & SiO\({}_{2}\) (\%) & 21.57 & 71.24 & 4.48 \\  & Al\({}_{2}\)O\({}_{3}\) (\%) & 5.73 & 1.48 & 0.94 \\  & Fe\({}_{2}\)O\({}_{3}\) (\%) & 3.48 & 0.32 & 0.2 \\  & K\({}_{2}\)O (\%) & 1.05 & 3.5 & \textless{}0.01 \\  & MgO (\%) & - & \textless{}0.01 & \textless{}0.01 \\  & Na\({}_{2}\)O (\%) & - & 15.12 & 0.34 \\  & Loss on Ignition (L.OL. \%) & 1.5 & 0.58 & 41.81 \\ \hline \hline \end{tabular}
\end{table}
Table 2: Physical and chemical properties of OPC, GWP, and MWP.  
Figure 1: Gradation curve for fine aggregate according to ASTM C33.  
Figure 2: Visual appearance of (**a**) OPC, (**b**) GWP, and (**c**) MWP.