Durability of Bauxite-Waste Pozzolana Cement Concrete

The durability of calcined bauxite-waste pozzolana cement was evaluated against sulfate, seawater, and soft water attacks to establish acceptance criteria for forecasting its performance under anticipated environmental conditions during the lifetime of its concrete building.

The tests consisted of preparing mortar bars containing 10 to 40 percent addition or replacement of cement by the pozzolana and storing in sulfate solutions, seawater, and soft water. Measurements and recordings of defects of the mortar bars were taken for a period of about 3 years.

The most remarkable results were obtained from specimens of the pozzolana calcined at 900°C above optimum calcining temperature. The resuits obtained so far indicated that resistance to the various conditions was favorable for specimens with less percentage replacement or addition. But on the whole adding the pozzolana to the cement proved more successful than replacing it.