The effects of pozzolanic binders and polypropylene fibers on durability of SCC to magnesium sulfate attack

The effects of various pozzolanic binders such as silica fume, metakaoline and zeolite on self consolidating concrete (SCC) durability in magnesium sulfate environment were studied. Change in compressive strength, mass and dimensions of concrete specimens were measured after 6 and 9 months immersion in 5% and 10% magnesium sulfate solutions. In this study the effect of polypropylene fibers together with pozzolanic binders on SCC durability in sulfate environment were also investigated. To contrast the use of pozzolanic binders on internal characteristics of concrete, samples were observed by scanning electron microscopy (SEM). To evaluate the intensity of elements in paste compositions, energy-dispersive X-ray spectroscopy (EDX) tests were accomplished. Test results showed that metakaoline and zeolite have better effects than silica fume on durability of SCC to magnesium sulfate attack. The least expansion occurred in zeolite SCC. Applying polypropylene fibers reduced mass loss in specimens but not much effect was observed on volume expansion of specimens.