## 5 Results and Discussion
### Pore Solution Analysis  
The pore solution compositions of the selected specimens within the timeframe of 5 h-672 h are summarized in Table 4.  
Table 4 indicates that the concentrations of all aqueous species first underwent an increase and then a subsequent reduction of different magnitudes with the increasing curing period. The concentration of Na + K peaked at 168 h in the CS specimen and at 24 h in the JA8, JA12, PNS12 and PNS18 specimens, while the highest concentrations of the other aqueous species occurred at 10 h. The concentration increases in the early stages were mainly attributed to the reactant dissolution (Equations (6)-(8)), while the prolonged concentration increase in Na + K was due to the cation exchange reaction between the Ca\({}^{2+}\) that was released from the clinker dissolution and the exchangeable Na\({}^{+}\) and K\({}^{+}\) in the soil minerals (in Equation (9), \(\Theta\)! refers to a single soil mineral and M = Na or K). Then, the precipitation of the cement hydrates (Equation (10)) and the pozzolanic reaction products \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Curing Period** & **Na + K** & **Na** & **Si** & **Al** & **Ca** & **SO\({}_{4}^{2-}\)** & **OH\({}^{-}\)** \\ \hline \multicolumn{6}{c}{CS (no admixture)} \\  
\hline \hline \end{tabular}
\end{table} 
Table 4: The pore solution composition (mmol/kg) of the selected specimens. (Equation (11)) continuously consumed the aqueous species, thereby reducing the total concentration of Na + K.  
\[\text{Na}_{0.33}\text{Al}_{2.33}\text{Si}_{3.67}\text{O}_{10}( \text{OH})_{2}+2\text{OH}^{-}+7.34\text{H}_{2}\text{O}\to 0.33\text{Na}^{+}+2.33 \text{Al}(\text{OH})_{4}^{-}+3.67\text{H}_{4}\text{SiO}_{4} \tag{6}\] \[\text{CA}+\text{a}\text{H}_{2}\text{O}\to\text{xCa}^{2+}+\text{yNa}^{+ }+\text{zOH}^{-}+\text{wSO}_{4}^{2}+\text{nAl}(\text{OH})_{4}^{-}\] (7) \[\text{C}_{3}\text{S}+\text{C}_{2}\text{S}+\text{C}_{3}\text{A}+1 \text{H}_{2}\text{O}\to\text{8 Ca}^{2+}+10\text{OH}^{-}+2\text{H}_{2}\text{SiO} _{4}^{2}+2\text{Al}(\text{OH})_{4}^{-}\] (8) \[\Theta\Big{|}_{\text{M}}^{\text{M}}+\text{Ca}^{2+}\to\Theta\left| \text{Ca}+2\text{M}^{+}\right.\] (9) \[\text{5 Ca}^{2+}+6\text{OH}^{-}+2\text{Al}(\text{OH})_{4}^{-}+\text{ H}_{2}\text{SiO}_{4}^{2-}\to\text{CSH}+\text{CAH}+\text{Ca}(\text{OH})_{2}\] (10) \[\text{5M}(\text{OH})_{2}+2\text{Al}(\text{OH})_{4}^{-}+4\text{H}_{ \beta}\text{SiO}_{4}^{b-4}\to\text{MASH} \tag{11}\]  
Compared to the CS specimen, the addition of JA at a dose of 0.8% significantly improved the concentrations of all aqueous species, which was partly attributed to the accelerated dissolution of the cement clinkers [37] and the soil minerals [38] by the appropriately increased pH value. According to Equation (7), another reason for the concentration increases in Na + K, Al, Ca, SO\({}_{4}^{2-}\) and OH\({}^{-}\) was the JA dissolution. When the JA dose was increased to 1.2%, the concentrations of Na, Al and OH\({}^{-}\) further increased, but the increases in the Si and SO\({}_{4}^{2-}\) concentrations were lowered and the concentrations of Ca and K reduced to lower than those in the CS specimen. These results were related to the solubility of the ions in the pore solution and the compositional minerals of JA. As JA was composed of several minerals, the soluble minerals with smaller component ionic radii (e.g., Na\({}^{+}\) and OH\({}^{-}\)) dissolved preferentially, thus limiting the dissolution of minerals with larger component ionic radii in either the JA or the raw materials (e.g., C\({}_{3}\)S and C\({}_{3}\)A in the clinkers). Furthermore, the reduced Ca concentration weakened the cation exchange reaction (Equation (10)), thereby lowering the K concentration. Meanwhile, the promotion effects of the high OH\({}^{-}\) concentration in the soil mineral dissolution still existed and, therefore, maintained Si and Al concentrations at high magnitudes.