A lightweight structural concrete includes a hydraulic binder; effective water; a superplasticizer; and aggregates; the concrete having a density in the fresh state varying from 1.40 to a Dmax value calculated according to formula (I) Dmax=1.58+(a×AM) in which “a” represents a coefficient for which the value is equal to 1; “AM” represents the mass percentage of the amorphous materials contained in 1 m3 of fresh concrete; the concrete having a maximum fresh state density Dmax less than or equal to 1.85; the concrete having a Weffective/L ratio varying from 0.19 to 0.46, where Weffective represents the quantity of effective water in kilogram per cubic meter of fresh concrete; “L” represents the quantity of cement and additions in kilograms per cubic meter of fresh concrete; the concrete including a quantity of effective water varying from 100 to 230 liters per cubic meter of fresh concrete; the concrete including a quantity of Portland clinker greater than or equal to 150 kilograms per cubic meter of fresh concrete; the concrete including a quantity of (Portland clinker+optionally fly ash+optionally slags+optionally silica fume+optionally calcined shale+optionally calcined clays) greater than or equal to 300 kilograms per cubic meter of fresh concrete; the concrete having a volume of paste greater than or equal to 300 l/m3 of fresh concrete; the concrete including from 1 to 16% by volume of air.