Effect of Investigation viscosity modifying admixtures and Lime stone Powder Combination on Fresh and Hardened Properties Self Compacting concrete

By 1988 in Japan,SCC(Self-Compacting Concrete) is developed and defined as a high capable flowability concrete without requirement of vibrator runs.Generally, SCC based on the materials used to modify its viscosity, can be divided into three categories;first:the powder type SCC, second:the VMA(Viscosity Modifying Admixtures ) type SCC and the third group that includes a mixture of SCC.In this research, 5 SCC projects were built using the VAM-type SCC and lime stone powder- type SCC,separately and also using the combination of both VMA-type SCC and lime stone powder-type SCC.In order to determine the possibility of viscosity in the projects, the VAM-type SCC has been used in the following percentages: 0.05 , 0.1, 0.15 and0.2 based on which the weight of cement are used as a substitute for lime stone powder-type SCC. The new mixtures were tested using different rheological states experiments such as the Slump, T 50, V- Funnel, V- Funnel at T: 5 Minutes, J-Ring and L-Box to set the standard range of self-compacting characteristics. After approval, in this section, the Projects were examined to determine the compressive strength at the age of 7 and 28 days. In addition, the effects of the VMA-type SCC and lime stone powder-type SCC with different proportions, were evaluated and compared in the fresh and hardened concrete experiments.The results showed an increase in the VMA- type SCC, in the subject of making bubbles and also a decrease in the specific gravity up to12.9percent, as well as the compressive strength has fallen up to60percent in maximum.