Cementitious materials for construction-scale 3D printing: Laboratory testing of fresh printing mixture

The past and future of sustainable concrete: A critical review and new strategies on cement-based materials

Screening of bacteria and concrete compatible protection materials

Utilization of red mud derived from bauxite in self-compacting concrete

An investigation on the use of zeolite aggregates for internal curing of concrete

Self-consolidating concrete (SCC) is one of the innovative products in concrete technology that has been developed in recent years. However, many researchers are still trying to optimize the mixture proportions and investigate the incorporation of new materials in SCC. The typical high content of portland cement in SCC is one of the main challenges in optimization of its mixture proportions. This high cement consumption increases the production cost of SCC and, considering the large amount of CO2 emitted during portland cement production, is also undesirable from an environmental point of view. In this study, two approaches were employed to lower the portland cement content in SCC mixtures, namely, adopting a dense aggregate grading and partially replacing portland cement with natural zeolite. Portland cement was replaced by natural zeolite at different percentages to investigate the effect of this natural pozzolan on the fresh and hardened properties of the SCC mixtures. Fresh properties of the S...

Use of Natural Zeolite to Produce Self-Consolidating Concrete with Low Portland Cement Content and High Durability

Dissimilar Joining of Al/Mg Light Metals by Centrifugal Compound Casting Process

Compound casting is an efficient method for bonding dissimilar metals, in which a dramatic reaction can occur between the melt and solid. The centrifugal casting process, a type of compound casting, was applied to cast Al/Mg dissimilar bimetals. Magnesium melt was poured at 700°C, with melt-to-solid volume ratios (Vm/Vs) of 1.5 and 3, into a preheated hollow aluminum cylinder. The preheating temperatures of the solid part were 320, 400, and 450°C, and the constant rotational speed was 1,600 rpm. The cast parts were kept inside the casting machine until reaching the cooling temperature of 150°C. The result showed that an increase in preheating temperature from 320 to 450°C led to an enhanced reaction layer thickness. In addition, an increase in the Vm/Vs from 1.5 to 3 resulted in raising the interface thickness from 1.2 to 1.8 mm. Moreover, the interface was not continuously formed when a Vm/Vs of 3 was selected. In this case, the force of contraction overcame the resultant acting force on the interface. An interface formed at the volume ratio of 1.5 was examined using scanning electron microscopy (SEM) equipped with energy-dispersive X-ray spectroscopy (EDS), and the results demonstrated the formation of Al3Mg2, Al12Mg17 and (δ+Al12Mg17) eutectic structures in the interface. 

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Morteza Sarvari

Papers

Use of Natural Zeolite to Produce Self-Consolidating Concrete with Low Portland Cement Content and High Durability

Dissimilar Joining of Al/Mg Light Metals by Centrifugal Compound Casting Process

Effect of melt-to-solid volume ratio and preheating temperature on Mg/Al bimetals interface by centrifugal casting