الفهرس 
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Abstract
1:-Introduction: - Lightweight high strength self-compacting concrete (LHSCC) is a new type of concrete that combines features of light weight concrete (LWC), high strength concrete (HSC), and self-compacting concrete (SCC). Light weight concrete can make easily by the use of lightweight aggregate like pumice result a reduction in the dead weight of a construction. It is also possible to reduce steel reinforcement. Self-compacting concrete that can flow under its weight and completely fill the formwork, without the need of any vibration, while maintaining homogeneity. Light weight concrete characterized by density, high strength concrete characterised by high compressive strength, and self-compacting concrete is characterised by high workability. By using available materials in Egypt, a composite concrete produced which has the properties of light weight concrete, high strength concrete, and self-compacting concrete 2:- Research scope: - The scopes of this research is producing lightweight high strength self-compacting concrete and study the properties of concrete in the case of fresh and hardened. 3:- Research objective: - The objectives of the research work to produce lightweight high strength self-compacting concrete by using locally available materials in Egypt like pumice aggregate that will provide an advantage of reducing dead weight of a structure, and study the properties of concrete in the case of fresh and hardened. 4:- Steps Study: - To achieve the goals of the study five samples were designed. The fresh properties (filling ability, passing ability and segregation resistance) measured by using slump flow, T500, L-Box and GTM screen stability. The hardened properties measured by the compressive strength, splitting tensile strength, flexural strength and modulus of elasticity. 5:- Summary of Study: - The results have shown that natural pumice aggregate can be satisfactorily utilized in the production of lightweight high strength self-compacting concrete with 28-day compressive strengths 52 MPa and showed that increase of pumice aggregate reduces the workability generally with a note that all mixtures achieved requirement of EFNARC, 2005, JSCE for self-compacting concrete except M1. The compressive strength of concrete is a function of the relative proportion of paste to aggregate. It is concluded that, decreasing pumice volume and increasing the cement paste content would increase compressive strength. Increasing in cement content by 100 kg/m3 would increase in compressive strength 15 to 23% For the same cement content in mixtures M4 and M5, increasing of fine (sand)/coarse(pumice) aggregate ratio by 10% lead to increasing of compressive strength by 11%.The indirect tensile strength, flexural strength and modulus of elasticity increases with increase in cement content and decrease in pumice volume.