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Lightweight foamed concrete (LWFC) is.Foamed concrete is produced either by a prefoaming or a mixed foaming method. The prefoaming method involves the separate production of base mix cement slurry (cement paste or mortar) and a stably preformed (foaming agent with water) and then the thorough blending of this foam into a base mix. In mixed foaming, the surface-active agent is mixed with the base mix ingredients and foam is produced during the mixing process, resulting in a cellular structure in the concrete [3]- [5]. Structural lightweight concrete (SLWC) is similar to normal-weight concrete except that it has a lower density [6]. SLWC is defined as a concrete having a compressive strength of up to 17 MPa with a bulk density less than 1950 kg/m 3 ; structural lightweight concrete can be 25 % lighter than normal-weight concrete but have a compressive strength of up to 60 MPa [7]. The term high-performance concrete (HPC) is used for concrete mixes that possess the following three properties: highworkability, highstrength and high durability [8].Plain concrete is a brittle material, which results in poor fracture toughness, poor resistance to crack propagation and low impact strength. This inherent brittleness has limited its application in fields requiring high impact, vibration and fracture strengths. Fibres are used to modify the tensile and flexural strengths, toughness, impact resistance and fracture energy, and to arrest crack formation and propagation and thus improve strength and ductility [9]-[12]. Glass fibres improve the strength of the material by increasing the force required for deformation and enhance the toughness by increasing the energy required for crack propagation [13]. Ghorpade [14] investigated the effect of glass fibre on high-performance concrete with silica fume as an admixture. The maximum percentage increase in compressive strength was observed at 1 % fibre and 10 % silica fume content. The flexural strength increases with up to 1 % of fibre volume, thus, the strength decreases. Polypropylene fibres are the most popular of the synthetics. They are chemically inert, hydrophobic and lightweight. Polypropylene fibres reduce plastic shrinkage cracking and subsidence cracking over steel reinforcement [6]. Banthia and Gupta [15] investigated the influ-

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