الفهرس 
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Abstract
Most concrete currently used in civil engineering construction has to be compacted in order to achieve the required strength and durability. Vibration treatment, as soon as the concrete has been laid, is the most common method for achieving strength, but it costly, causes delays and presents a serious health and safety risk. Self compacting concrete (SCC) is a special concrete that does not require vibration treatment. Development of high-performance SCC involved using high paste volume (and low aggregate volume) to promote high deformability and reduce the risk of blockage and segregation during concrete placement. The water-to-cementitious materials ratio (W/CM) was selected as a function of the targeted compressive strength.
Most studies on SCC deal with mixture proportioning and characterization of fresh-and hardened- concrete properties with limited information on structural performance. Columns as an important structural element have more interest in investigation their behavior in SCC mixes, this is came from the fact that using standard vibration techniques with conventional concrete that is not fluid enough in congested sections with high-density reinforcement, such as those in columns in moment-resisting frames in seismic areas or confined columns with high volumetric reinforcement ratio in high rise buildings and bridge columns, may lead to some surface and structural defects resulting from lack of proper bond development between the concrete and the reinforcement as well as the entrapment of air voids in the concrete. Air voids in concrete mean the ingress of substances that can initiate or propagate possible deleterious actions and lack of bond between the concrete and reinforcement mean producing of columns, and consequently a structure, with less ductility.
SCC, such concrete is proportioned to exhibit a low yield value and a moderate viscosity to maintain high deformability and compacted into every comer of the column formwork with minimum segregation by means of its own weight and without the need for vibrating compaction, will enable engineers of producing a confined columns with high longitudinal and transverse reinforcement ratio with high axial load capacity and enhanced ductility without the problem of durability and ductility in conventional concrete columns.
As SCC is relatively a new material has a different characteristics than conventional concrete because the requirements of high volume binder to aggregate ratio which