| Abstract: |
Self-Compacting Concrete (SCC) is a new category of High PerformanceConcrete with high workability and flowability but without segregation. Thisconcrete has the advantages of being cast easily under its own weight without theneed of any external compacting energy. In addition, SCC is made of sameingredients of Normal Concrete (NC) in addition to extra fine material and specialtype of super-plasticizer.The current research studied the properties of SCC containing differentpowders types (fly ash, silica fume and metakaoline) and different aggregate types(gravel, basalt and dolomite) compared with that of SCC without any powders.The research program consists of 48 concrete mixes and divided into 6groups. All mixes were designed to have a constant water/powder ratio of 0.45 anda constant content of super-plasticizer (sikavisco-crete 5920) of 1.5% by weight ofpowder, a trial mixes were done to obtain the previous ratios to ensure the self-compactability conditions. And all mixes were made from locally availablematerial.Fresh properties of SCC were tested and the results indicated that all mixessatisfied the EFNARC limitations for slump flow time (Tso), slump flow diameter(D), the L-box height ratio (H2/Hj), and V -Funnel flow time. Also the hardenedproperties of SCC were tested and the results indicated that, mixes containingdolomite as a coarse aggregate gave the highest values for both compressive andtensile strength on the other hand, mixes containing gravel as a coarse aggregategave the lowest values. Also, the results indicated that incorporating FA decreasethe compressive strength at 3 days and show an increase at 28 days , while SFincrease the compressive strength at 3 and 28 days and MK show an increase atearly ages and a slight changes at 28 days. And the incorporation of theses powdershas a little effect on tensile strength.IIABSTRACTSelf-Compacting Concrete (SCC) is a new category of High PerformanceConcrete with high workability and flowability but without segregation. Thisconcrete has the advantages of being cast easily under its own weight without theneed of any external compacting energy. In addition, SCC is made of sameingredients of Normal Concrete (NC) in addition to extra fine material and specialtype of super-plasticizer.The current research studied the properties of SCC containing differentpowders types (fly ash, silica fume and metakaoline) and different aggregate types(gravel, basalt and dolomite) compared with that of SCC without any powders.The research program consists of 48 concrete mixes and divided into 6groups. All mixes were designed to have a constant water/powder ratio of 0.45 anda constant content of super-plasticizer (sikavisco-crete 5920) of 1.5% by weight ofpowder, a trial mixes were done to obtain the previous ratios to ensure the self-compactability conditions. And all mixes were made from locally availablematerial.Fresh properties of SCC were tested and the results indicated that all mixessatisfied the EFNARC limitations for slump flow time (Tso), slump flow diameterCD), the L-box height ratio (H2/H,), and V -Funnel flow time. Also the hardenedproperties of SCC were tested and the results indicated that, mixes containingdolomite as a coarse aggregate gave the highest values for both compressive andtensile strength on the other hand, mixes containing gravel as a coarse aggregategave the lowest values. Also, the results indicated that incorporating FA decreasethe compressive strength at 3 days and show an increase at 28 days , while SFincrease the compressive strength at 3 and 28 days and MK show an increase atearly ages and a slight changes at 28 days. And the incorporation of theses powdershas a little effect on tensile strength.
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