Lightweight concrete can offer economical advantages for engineering applications. Compared to normal weight concrete, with a density ranging from 140-150 lbs/ft3, structural lightweight concrete has an in-place density of 90-115 lbs/ft3. Structural lightweight concrete mixes can be designed to achieve strengths, durability and other performance characteristics that are similar to normal weight.
Added to this, structural lightweight provides more efficient strength-to-weight ratios, allowing for smaller load-bearing elements such as footings and columns, less reinforcing steel and a lower volume of concrete. This in turn helps to achieve lower project costs.
In buildings, structural lightweight concrete often ensures a structure with higher fire-ratings and higher R-values for walls because of improved insulation properties. Structural lightweight concrete has been used successfully for bridge decks, piers and beams, slabs and wall elements in both steel and concrete frame buildings. In addition, it is also used for parking structures, topping slabs and composite slabs on metal decks. Any concrete mixture considered for a specific application should always be evaluated for the service environment in which it will be placed.