This research deals with the effect of rice husk ash (RHA) and Metakaolin (MK) as a partial replacement for ordinary Portland cement (OPC) on properties of self – compacting concrete (SCC). Three different replacements of RHA ( 5% , 10% and 15%) and one replacement of Metakaolin (15%) were used for SCC.
To determine the workability, three test methods were adopted, slump_flow, and V_funnel.
The experimental results showed that (RHA) improved the strength and modulus of elasticity of SCC at age after 60 days . The optimum strength was at 15% replacement . Specimens with 15 % replacement of ( MK) showed a better strength and modulus of elasticity at all ages . Also the use of( RHA and MK) caused reduction in water absorption and increase the ultrasonic pulse velocity.