Lightweight Self-Compacting Concrete Using Lightweight Expanded Clay Aggregate

The aim of the research is to find out the performance of lightweight self-compacting concrete (LWSCC) made with (25%, 50%, 75%, 100%) lightweight expanded clay aggregate (LECA) as replacement percentage by volume of natural weight coarse aggregate. Ten mixes were made, five of them contain (LECA) with (25%, 50%, 75% and100%) and without fibre. The other five mixes contain (LECA) with the same percentages and with (0.1%) polypropylene fibre. The characteristics of hardened and fresh were checked by series of testing methods including UPV test, water absorption, flexural strength, splitting tensile strength, compressive strength, fresh density, V-funnel,  L-box, and slump flow. The slump flow for all mixes was kept at (665-731) mm; the results showed that the fresh density of LWSCC was varied from 1956- 2475 kg/, which decline with increasing LECA content. With increasing the percentage of LECA, the V-funnel flow time was increased while decreased,while they increased when polypropylene fibre is used. The results also demonstrated that flexural strength, splitting tensile strength and compressive strength were lower when increase the percent of LECA, and generally enhanced as the fibre used. The water absorption was increased, and dry density was reduced with increasing the percent of LECA. This increase is reduced slightly by adding fibre at the same time, and it has no apparent effect on the dry density.