• Adnan Flayih Hassan Al-Sibahy, Dr. Civil Engineering Department\ the University of Al-Qadisiya\ Iraq
Keywords: Superplasticizer admixture, lightweight aggregate concrete, metakaolin, recycled glass, mechanical behaviour


This paper presents an experimental investigation of the effect of a superplasticizer admixture on the mechanical behaviour of expanded clay lightweight concrete containing metakaolin material and recycled glass aggregate. The optimum dosage of the superplasticizer admixture (type SNF) was adjusted and used by weight of cement. The short and long-term mechanical properties of concrete mixes were measured in accordance with the relevant British / EN standards. The obtained results were compared with the results of control concrete mixes (without superplasticizer).
The results obtained showed that the superplasticizer admixture exhibited a 20% reduction in content of mixing water. All measured values of unit weight, compressive and splitting tensile strengths increased when the superplasticizer admixture is used. The concrete mix containing 30% recycled glass revealed an increase in the mechanical strength compared with the mix of 15% recycled glass. However, the workability of the superplasticizer concrete mixes was degraded, reaching 44% reduction in slump value.


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