Leca Concrete
structural Lightweight Concrete
Iran is considered one of the earthquake-prone regions in the world, making the lightweighting of buildings to enhance earthquake resistance particularly important. The use of concrete, as one of the most widely used construction materials in structural buildings, has always faced the challenge of being heavy.
Structural lightweight concretes are concretes that, despite having a density of less than 2000 kg/m³, achieve a compressive strength of over 17 MPa. Producing these concretes is only possible using strong and lightweight aggregates. The highest strength of lightweight concrete is achieved when structural lightweight aggregates, whose strength is equal to or greater than that of the cement matrix, are used for reducing the concrete’s weight.
In 2006, Leca Company succeeded in producing structural lightweight aggregates in Iran through process modifications. Further scientific research on this product is ongoing, and it is undergoing the required period for obtaining technical approvals for widespread use.
Non-Structural Lightweight Concrete
Lightweight concretes with a compressive strength of less than 7 MPa are classified as non-structural lightweight concretes. These concretes, with a density of 800 kg/m³ or less, are highly effective as partition walls and as thermal and sound insulation in floors.
This type of concrete can be used in combination with other materials in walls, floors, and various ceiling systems. Adding normal-weight fine aggregates increases the concrete’s weight and strength. However, to achieve thermal insulation properties (low thermal conductivity), the maximum density is limited to 800 kg/m³. When producing and using non-structural lightweight concrete, the goal is to enhance thermal insulation by reducing weight. It is important to note, however, that as the concrete’s density decreases, its strength also decreases. Compressive strength and density are closely related, with higher density generally resulting in greater strength. The intended application of this type of concrete is determined based on the achieved strength.