Effect of Excessive Bleeding on the Properties of Cement Mortar

The bleeding of cementitious materials corresponds to the settlement granular skeleton accompanied by accumulation water at surface (bleed water). Part this (internal bleeding) remains trapped under aggregates (sand or gravel) reinforcements. excess can weaken bond between matrix and (or reinforcements), which affects mechanical performance durability material. This study aims investigate effect excessive induced superplasticizer on properties mortars. For this, a cement paste in presence was carried out. effects water-to-cement ratio (w/c) (SP) dosage have been characterized. Then, influence proportion sand examined varying sand/cement (s/c) ratio. determined difference external corresponding mortar. results show that internal increases with s/c SP dosage, until it reaches plateau. porosity mortar were then examined. Microscopic observations made assess quality paste/sand bond. showed causes degradation (a more porous bond), resulting decrease strength (by 30% for compressive 25% flexural strength) hardened