关键词: pH值, 石灰石粉, 硫酸镁, 盐酸, 复合侵蚀

Abstract:

To research the anti-erosion performance of mortar containing the limestone powder, the cement pastes and mortars with different contents of limestone powder were prepared and soaked into the hydrochloric acid and magnesium sulfate complex erosion solution. The change of pH value of solution was tested by pH tester, while the strength test and X-ray Diffraction were carried out to study the variation of the strength of the mortar containing limestone powder and the erosion products under complex erosion time. The testing results show that the pH changes rapidly at the early stage and later slowly. Before 28 d erosion, the strength of the mortar increases, then declines with the increasing dosage of limestone powder after 28 d erosion. The process of erosion is acid reactions with calcium hydroxide and calcium carbonate while the erosion of magnesium ions is not obvious. Furthermore, because of the existence of sulfate ion, the gypsum is generated, which slows down the erosion process.

Key words: limestone powder, magnesium sulfate, hydrochloric acid, complex erosion