PROPERTIES OF STRUCTURAL LIGHTWEIGHT HIGH STRENGTH SELF-COMPACTING CONCRETE.

Combining structural lightweight concrete and self-compacting concrete advantages is a significant challenge in modern concrete technology research. The density of concrete can be reduced by using lightweight aggregate. Consequently, structural self-weight is also reduced. Porous lightweight aggregates have low compressive strength, which presents a challenge in developing high-strength structural lightweight self-compacting concrete. The strength and weight of self-compacting concrete can be enhanced to obtain a special concrete with multiple benefits. Pumice from North Sinai in Egypt was used as a locally available natural lightweight aggregate. The properties of the concrete produced were studied at fresh and hardened states in different proportions of partial replacement of dolomite with pumice to find the optimum replacement percentage. The optimum mix has a high strength of 60 MPa and 1.98 g/cm2 unit weight, which is considered structural lightweight concrete and high strength. Moreover, it has self-compacting concrete characteristics. Results showed that the workability of self-compacting concrete increased with the decrease of concrete unit weight. [ABSTRACT FROM AUTHOR]