Durability-related properties

Internal sulfate attack in mortars containing contaminated fine recycled concrete aggregates

“…On the other hand, increasing the alkalinity of the mix or using a lower sulfate content seemed to limit the swelling results. This indicates that the maximum sulfate content established in EN206 may be too strict, which is in line with the findings of the PN RecyBéton [21] and their subsequent proposal to set this limit at 0.3%. Unrelated to their influence on the swelling amount, the variation of these parameters also changed the compressive strength of the mortars.…”

“…At these quantities, sulfates are considered the limiting reagent in the ettringite formation reaction so any augmentation would hypothetically lead to more swelling. The conclusions of recent durability studies indicate a level of 0.3% should be made possible [21].…”

Recycled aggregate concretes – A state-of-the-art from the microstructure to the structural performance

“…The carbonation of RAC has been well investigated in the literature [105]- [112]. The effects of the recycled aggregate incorporation on the carbonation thickness is related to different factors:…”

“…-The replacement ratio of recycled aggregates [107], [113] -The cement amount [78] -The characteristics of the old concrete from which the recycled aggregates are obtained [111] -The quality of the recycled aggregates (presence of asphalt materials, bricks, glass, concrete etc.) [112] -The type of crushing [96] -The curing [114] -The use of superplasticizer to reduce the Water/Cement ratio [115] There are a heterogeneitiy in the results obtained from different studies in literature, however the following conclusions were observed [105], [110]:…”

Valorization of Fine Recycled Aggregates Contaminated with Gypsum Residues: Characterization and Evaluation of the Risk for Secondary Ettringite Formation

“…To keep the risk for secondary ettringite formation at a reasonable level, the current water soluble sulfate limit in coarse recycled aggregates is established at 0.2% by EN 206 [29], with no specific mention of FRA. The conclusions of recent durability studies indicate a higher level should be made possible [30], specifically up to contents of 0.3% [31].…”