Influence of Viscosity Modifying Admixture (VMA) on the Properties of SCC Produced Using Locally Supplied Materials in Bahrain

The reluctance in utilizing the advantages of Self Compacting Concrete (SCC) in Bahrain stems from two contributing factors: Lack of research or published data pertaining to locally produced SCC, and a feeling of doubt and uncertainty in the minds of practicing engineers about reliability and suitability of SCC in hardened stage. The primary aim of this study is to explore the influence of viscosity modifying admixtures available in Bahrain on the fresh and hardened properties of SCC. For this purpose, three self-compacting concrete mixes and one control mix were prepared with same water/powder ratio and other ingredients, but with different fluidity. Control mix is considered to compare the strength of SCC with that of the normal concrete. The fluidity was varied by altering the dosage of VMA in different SCC mixes. The filling ability, passing ability and resistance to segregation were evaluated to make sure that prepared mixes satisfy the SCC basic criteria. From each SCC mix and control mix, 9 cubes were cast to obtain compressive strength of SCC in hardened stage after 3, 7 and 28 days of curing. Also, for each SCC mix and control mix, three prisms were cast and their flexural strength was tested after 28 days of curing. The test results of the specimens were used to carry out a comparison of compressive and flexural strength of different mixes of SCC and the control mix. The study shows that SCC prepared using locally supplied materials is also equally reliable as conventional concrete, provided that it satisfies all the basic requirements of SCC in fresh stage and maintains a minimum slump flow of 600 mm.