Fayza
Eisa E.Hekal
Manar M.Abdel Naby
Faten Selim
Abstract
In the present study, field examinations are explored on diversed blended cement mixes. The hardened blended pastes are prepared using ordinary Portland cement (OPC), fine metakaolin (MK) and brine chlorine sludge (CLS). Cement fouling features and the attack by SO4-2 ions are studied on the blended samples that are immersed in the marine environment up to 9 months. The performance of the cured specimens was explored via studying the compressive strength, the percent of mass change and the volume expansion at various curing durations. Beside, the total chlorophyll colonized on the surface of the cured specimens was determined by using spectrophotometeric technique . XRD and SEM techniques are used for studying the phase compositions and the morphology of the formed cement hydrates. The results illustrate that the blended mixes show an antifouling behavior higher than the neat OPC. This is related to acquiring a more compact structure of reduced porosities upon OPC blending. Additionally, OPC-MK specimens showed a high resistivity to attack by SO4-2 ions than OPC-CLS or neat OPC pastes. This is related to the high pozzolanic properties of MK in contrary to brine sludge
Keywords
Blended cement, Sulfate ions attack, cement bio-fouling
