DAMAGE EVALUATION OF TWO DIFFERENT CONCRETE MIX DESIGNS CONTAINING SULFIDE-BEARING AGGREGATES

摘要

The DRI method aims at quantifying the concrete deterioration and it is necessary to adapt the features observed to the mechanism responsible for the deterioration observed. Some of the difficulties observed, when performing the DRI analysis of the samples affected by iron sulfide oxidation and internal sulfate attack, were to quantify/rate the damage observed in the aggregate particles. Sometimes the particles were disintegrated or corroded, thus making almost impossible to distinguish the cracks. The most important differences observed between the two kinds of concretes were the cracks in the cement paste, which were more pronounced in the 32MPa concrete, as well as the abundance of disintegrated aggregate particles.