BTL Lightweight Concrete
BTL Lightweight Concrete Solutions Ltd obtains its chemistry and machinery from Europe and the UK. The companies involved have been actively promoting the use of their foamed concrete product for the past 25 years, all over the world. It is mostly used in commercial and residential construction, either as pre-cast or in-situ poured buildings.
The process involves adding a specified quantity of pre formed foam (generated by mobile unit) to a specified mix design essentially comprising sand and cement to form a thick slurry. Once the foam has been added and folded into the initial slurry, the resultant mix is very flowable and virtually self-leveling.
The pre-formed foam is produced by a generator using a prescribed mix of water and air under pressure with a foaming agent. The environmentally safe foaming agent produces a very stable and long lasting foam. This is important to avoid premature foam collapse before the concrete has achieved green strength.
Once the concrete has cured, the foam disappears and the concrete mass results in a closed cell structure of millions of air cells within the concrete mass (lighter densities float).
Different final densities of concrete can be achieved by adjusting the proportions of the initial slurry and varying the quantity of the foam to the slurry. Densities are capable of between 300 kg/M³ to 2000kg/M³ and strengths from 1Mpa to 35 Mpa.
Lightweight foamed concrete has a number of applications due to its nature of being not only lighter but also warmer and quieter.
Density 300 – 600 kg/m³:
This density is primarily applied for thermal insulation or fire protection. It uses only cement (or little sand), water and foam and can easily be pumped. The foam generators allow the production of stiff foam for slopes to be applied on rooftops.
Density 700 – 800 kg/m³:
This density is also used for void filling, such as landscaping (above underground construction), to fill voids behind archways and refurbishing of damaged sewerage systems. This density is also used to produce building blocks.
Density 900 – 1100 kg/m³:
This is used to produce blocks and other non-load bearing building elements such as balcony railings, partitions, parapets and fence walls etc.
Density 1200 – 1400 kg/m³:
These are the most common densities for prefab and cast in situ walls, load bearing and non-load-bearing. It is also successfully used for floor screeds (sound and insulation plus weight reduction).
Density 1600 – 1900 kg/m³:
Recommended for slabs and other load-bearing building elements where higher strength is obligatory.
Lightweight foamed concrete is self-compacting and does not require vibration, and is virtually self leveling. The inclusion of millions of air bubbles in the initial slurry behave like ball bearings to enhance flowablity.
|Density kg per cu. metre||MPa (compressive strength)||R Value (1000 mm)|