Deterioration mechanism of plain and blended cement mortars partially exposed to sulfate attack

摘要

The degradation of cement-based materials partially exposed to sulfate solution are dramatically serious than under ordinary full immersion. To research the damage regime of cement-based materials partially exposed to sulfate attack, the resistance of drying (upper) portion and immersed (lower) portion of both the plain cement mortars as well as fly ash (FA) and grounded blast furnace slag (GBFS) modified cement mortars partially immersed in 10% Na2SO4 solution was investigated in this paper. The mass change, relative dynamic modulus of elasticity, compressive/flexural strength and water-soluble SOi-contents were monitored to show the damage progress. SEM/EDS, XRD, MIP and X-CT were used to investigate the microstructure changing.