2.3.4. Chemical Resistance Testing

The evaluation of chemical resistance in CAM samples encompassed an extensive methodology. Samples were subjected to acidic and alkali environments in accordance with ASTM C267 [25] and ASTM C289 [26] standards, respectively. For the acid resistance test, CAM specimens were immersed in a sulfuric acid (H₂SO₄) solution with a pH value of 1.0 (see Figure 5d). The exposure duration was rigorously controlled at 28 days to ensure a thorough assessment of acid resistance. Conversely, the alkali resistance test involved immersing CAM specimens in a sodium hydroxide (NaOH) solution with a pH value of 13.0, also maintained for a duration of 28 days. The environmental conditions for both tests were controlled with precision, with the temperature held at 25 °C and the relative humidity at 95%, replicating real-world scenarios. These meticulous testing protocols provided quantitative data on CAM’s resistance to corrosive chemical environments, enhancing its applicability as a durable stabilization solution for ballast tracks. After the curing process, the UCS test was conducted on these cured specimens, measuring 50 mm in diameter and 100 mm in height. Three replicates for each mixture were used for comprehensive analysis.