The weight of the standard cement concrete mix ranges from 2200 kg/m3 to 2600 kg/m3. This is one of the major drawbacks of traditional concrete because this heavyweight of concrete renders it an uneconomic construction material. In order to improve the performance of concrete as a building material, attempts have been made to reduce the weight of standard concrete. Cement concrete with a free weight varying from 300 kg / m3 to 1850 kg / m3 is considered a lightweight concrete mix.
The strength of the lightweight of concrete depends on the density of the aggregate. Less porous aggregate, which is heavier in weight, produces stronger concrete, particularly with higher cement content. Aggregate grading, w/c ratio, and degree of compaction also influence the strength of the concrete.
The following are the main characteristics of lightweight concrete:
The density of this concrete ranges from 300 kg/m3 to 1200 kg/1m3. The lightest variety is suitable for insulation purposes, while the heavier variety is used for structural purposes. The low density of cellular concrete makes it ideal for precast roofing and flooring units. These lighter units are easy to handle and transport from the factory to the site.
In relation to its density, the compressive strength of cellular concrete is high. The compressive strength of such concrete was found to increase with an increase in its density. The tensile strength of cellular concrete is approximately 15 to 20 percent of its compressive strength.
The strength to mass ratio of cellular concrete is much higher than that of standard concrete. Thus, the weight of the roof slab and the cellular concrete floor is around 25% of standard reinforced concrete.
Due to the high strength-to-mass ratio and the low weight of cellular concrete goods, their use results in lower steel use. The composite floor building using precast lightweight concrete blocks and reinforced concrete grid beams result in substantial gains in cement and steel use.
This greatly lowers the expense of constructing roofs and floors. In the construction of roofs and floors, savings of about 15-20 percent compared to traditional construction can be made using this method of construction.
The benefits of lightweight-concrete are as follows:
- The lightweight of concrete decreases the dead load of the building.
- It subsequently increases the development of the design of the building.
- It reduces freight and storage costs.
- The weight of the structure on the foundation is an important factor in the design, particularly in the case of multi-story buildings and weak soils. The heavier dead load, deeper and tougher foundations involve higher costs.
- In framed buildings, columns and beams must hold tonnes of walls and floors. If the walls and floors are made of lightweight concrete, the foundations would also be lighter, resulting in significant savings in construction.
- The thermal conductivity of lightweight concrete is relatively low, which reduces the heat transfer from the roof and walls, resulting in lower indoor temperatures. This lower temperature gives the inhabitants warmth. The thermal conductivity increases with reduced density.
The lightweight of concrete can be used as follows:
- Like load-bearing masonry walls using cellular concrete blocks.
- As prefabricated floor and roof panels in all styles of buildings.
- As partition walls in all styles of buildings, such as residential, commercial, and institutional buildings.
- As insulating materials to exterior walls in all types of buildings, particularly office and industrial buildings.
- As a filler in the form of precast concrete wall panels in multistory buildings.
- Precast composite floors or wall panels, etc.
Expanded Clay Aggregate is on track with the goal of reducing the World’s carbon emissions and this lightweight concrete mix has restructured the concrete mixing technology with its applications and uses. So get in touch with them today and be a part of the Green revolution.