Hydrated lime is a historic material currently used in conservation. It hardens slowly by carbonation slowing construction however, supplementary cementitious materials accelerate hardening enhancing strength. Hydrated-lime mortars with rice husk ash–RHA-; ground granulated blastfurnace slag–GGBSand increasing amounts of two aggregates were studied. Increasing aggregate lowered strength as inte...

Cementitious materials are considered to be a waste form for the ultimate disposal of radioactive materials in geological repositories. We investigated by means of atomistic simulations the encapsulation of strontium-90, an important radionuclide, in calcium–silicate–hydrate (C–S–H) and its crystalline analog, the 9 Å-tobermorite. C–S–H is the major binding phase of cement. Strontium was shown ...

Ultra-high-performance concrete (UHPC) has superior mechanical properties and durability to normal strength concrete. However, the high amount of cement, high environmental impact and initial cost are regarded as disadvantages, restricting its wider application. Incorporation of supplementary cementitious materials (SCMs) in UHPC is an effective way to reduce the amount of cement needed while c...

Long-term predictions on the mobility and the fate of radionuclides and contaminants in cementitious waste repositories require a molecular-level understanding of the geochemical immobilization processes involved. In this study, the use of X-ray absorption spectroscopy (XAS) for chemical speciation of trace elements in cementitious materials will be outlined presenting two examples relevant for...

Supplementary cementitious materials (SCMs) and fillers play an important role in enhancing the mechanical properties durability of concrete. SCMs are commonly used self-consolidating concrete (SCC) mixtures to also enhance their rheological properties. However, these additives could have significant effects on viscoelastic Existing models for predicting creep drying shrinkage do not consider e...

As the premier material in construction industry across the world, concrete has major role in the effects of construction to our environment. Consumption of concrete is very high due to extensive use of concrete in many structural applications. The rapid infrastructural growth in developing countries and production of many by-product as waste material making high role to concrete producers in i...

Two groups of concrete mixtures, one without sodium sulfate and other with sodium sulfate, as an activator, were made with recycled powdered gypsum-wallboard for this investigation. Group 1 concrete mixtures were made using up to 20% of ASTM Class C fly ash and 20% powdered gypsum while Group 2 contained up to 60% of fly ash and 20% of powdered gypsum by mass. Relevant properties of concrete we...