Effect of Sulfate Attack on Compressive Strength of Foamed Cement Paste under Static Cyclic Loading

Abstract

Foamed cement paste has been increasingly used as backfill material in roadways and railway embankments due to its advantages of adjustable density and strength. The embankments constructed by foamed cement paste in coastal regions is subjected to both traffic loading and chemical erosion in service life. This paper conducted a series of durability tests to investigate the reduction of static and dynamic strength of foamed cement paste after the specimens were immersed in sodium sulfate solutions.The specimens were prepared with densities of 800 and 900 kg/m3. The influence factors of specimen density, concentration and cation type of sulfate solution on the strength degradation of the specimens were discussed. The results showed that the corrosion resistant coefficient of the specimens was reduced with the increase of immersion time and concentration of sodium sulfate solution. The degradation of the compressive strength under cyclic loading is more serious than that under static loading. The high density specimens perform better durability than low-density specimens, as the specimens with 900 kg/m3 under 28 and 56 days of sulfate attack had smaller reduction in both dynamic and static strengths than the specimens with 800 kg/m3.

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