Patent ID: 7658797

Claim:
A lightweight ready-mix concrete composition comprising 8-20 volume percent cement, 11-50 volume percent sand, 10-31 volume percent prepuff particles, 9-40 volume percent coarse aggregate, 10-22 volume percent water, and less than one percent by weight with respect to total weight of the composition of air-entraining agents; wherein the prepuff particles have an average particle diameter of from 0.2 mm to 3 mm, a bulk density of from 0.02 g/cc to 0.64 g/cc, an aspect ratio of from 1 to 3, and a continuous outer layer, wherein the sum of components used does not exceed 100 volume percent; wherein the concrete composition has a density of from 90 to about 130 lb./ft 3 ; wherein the slump value measured according to ASTM C 143 is from 2 to 8 inches; and wherein after the lightweight ready-mix concrete composition is set for 28 days, has a compressive strength of at least 1700 psi as tested according to ASTM C39.