Effects of Superplasticizer on the Properties of Fresh and Hardened Concrete Mixes

This research aims to study the effect of superplasticizer, when mixed with local materials, on both fresh and hardened concrete properties to achieve the demands of engineers and contractors. The methodology adopted to achieve the objectives of the research focuses mainly on a collection of data from different sources, an extensive review of previous studies, designing concrete mixes and implementing a lot of laboratory experiments using different ratios of superplasticizer with low water contents. The ratios of superplasticizer added were 0.0 (as a reference mix), 0.4, 0.8, 1.2 and 1.5 Litre/ 50Kg cement for concrete ages of 3, 7 and 28 days by preparing 12 cubes for each sample. Local ordinary Portland cement (OPC) and graded natural coarse and fine aggregate were used for all concrete mixes conducted in this research. From the experimental results obtained it has been found that the ratio of (0.8 litres per 50 kg of cement) superplasticizers with a reduction of 15% (w/c) showed a clear and significant effect on improving the workability of concrete mixes. Also the ratios of 1.5L per 50 kg of cement with a 30% reduction of (w/c(and 0.4L per 50 kg of cement with a reduction of 10% )w/c) superplasticizer have resulted in high workability. Whereas, the values of absorption showed no changes with respected to the used ratios of SP or w/c contents. The results have shown substantial improvement in the properties of concrete after use of the superplasticizers for achieving the lowest possible water/cement ratio while maintaining a high workability.