.

.6)

air

ρm

Traditional methods of lightweight concrete design are based on

preliminary assignment of cement consumption and volume concentration

of porous aggregate on the basis of empirical data, which take into

consideration strength and density of concrete, fresh concrete workability,

density and strength of aggregate. For this purpose both tabulated

reference data and corresponding regression equations can be used.

177

Volume concentration of coarse porous aggregate in lightweight concrete (ϕ)

can be found by formula (9.7) taking into consideration necessary stock of

cement-sand mortar between coarse aggregate grains (K ):

m

ρс

ϕ =