What is Cellular Concrete?
Cellular Concrete is generally defined as a lightweight cementitious material that contains stable air or gas cells uniformly distributed throughout the mixture at a volume greater than 20%. The cementitious materials encapsulate the air bubbles, then dissipate leaving a void structure as a replacement to traditional aggregate.
What are the advantages of pre-formed foam?
The pre-formed foam process offers excellent quality control and assurance of specified density. Preformed foam, unlike gas-forming chemicals, assures a consistent three-dimensional distribution of the engineered air cell system. Pre-formed foam produces a consistent matrix of relatively small air cells which are more desirable than a disorganized matrix of different size bubbles often created with the gas off method of reactive admixtures
What are the disadvantages of cellular concrete, compared to typical concrete?
In the lower density ranges cellular concrete does not develop the compressive strength of traditional concrete. While this may be a disadvantage in traditional concrete applications, it is an advantage in a cellular concrete application. It should be considered that cellular concrete and traditional concrete are typically used for different types of applications. Each form of concrete exhibits a unique family of performance characteristics. Each should be utilized in the appropriate type of project.
Is cellular concrete the same as CLSM
No! "Flowable" fill is typically a very wet cement and fly ash slurry mix. Although cellular concrete and CLSM flowable fill are fluid products, and are often both acceptable for the same application or project, cellular concrete exhibits less unit weight as well as enhanced sound and heat insulating properties. Often flowable fill reaches compressive strengths that make removal of the material problematic. Low density cellular concrete is very easy to remove with hand tools only.
Technically, cellular concrete is a controlled low strength material, but “CLSM” by definition, commonly refers to cement- fly ash slurries, while “cellular concrete” refers to the addition of an engineered air cell system to cement or cement/fly ash slurry.
AERFLOW™ from Aerix Industries is the answer to the demand for an air enhanced CLSM flowable fill product that can be produced at the Ready-Mix concrete plant. AERFLOW™ is an additive that may be added directly to the 1.5 – 2.0 inch slump flowable fill mix without the use of a foam generator. AERFLOW™ CLSM exhibits a high flowablity characteristics and 20-25% air content. CLSM flowable fill no longer needs high water contents and high ultimate compressive strengths. See the product section on AERFLOW™ for further details
Is cellular concrete the same as lightweight concrete?
Cellular concrete weighs considerably less than typical “lightweight” concrete. By definition “lightweight” concrete is a concrete made with aggregates that are substantially lighter than typical stone aggregates. Typically, lightweight concrete has a density + 120 lb. / cu.ft. Typical cellular concrete, utilizing the internal air cell structure instead of an aggregate, exhibits <20 - >60 lb. / cu. ft.
Is segregation a problem?
Unlike traditional concrete there is little to segregate in cellular concrete rendering segregation a moot point. The cellular concrete equivalent to segregation would be a collapse of the air cell system and a volume reduction in material. To prevent this one should use the most stable liquid foam concentrates and treat the mixed cellular concrete with some care in placing. Fresh cellular concrete is not fragile and can be pumped for long distances but conversely neither is it indestructible.