Documentation & Technical Specifications
The materials used for the production of a foamed concrete fall into three main categories which will effect a change in the wet and/or cured concrete.
We will assume the water has very little influence on the foamed concrete provided that the source is potable and it is therefore a constant. The three categories are:-
- Cement type
- Filler or aggregate
- Foaming agent
The strength of foamed concrete is generally accepted as being between 1 & 10 Newton/mm2. Strengths up to 25 Newton/mm2 at 1400kg/m3 have been produced in laboratory tests but are not commonplace in practice.
The effects of foamed concrete density, cement type and content, water/cement ratio, foam type and curing regime will influence the compressive strength.
The definition of a foamed concrete is one that has an air content of over 30% so typically the densities of foamed concrete range from 200kg/m3 to 1700kg/m3.
Densities below 400kg/m3 need to be attempted and undertaken with care, using specialized curing systems.
The Thermal insulation value for a material is its ability to resist the flow of heat across it. The measure of this heat flow rate is known as a materials K value and the lower this value the higher the products thermal efficiency.
The table below shows that broadly speaking the K value for foamed concrete lies between 0.08w/mk at the lower densities and 0.62w/mk at the higher densities.
The cement or binder is used to affect a set in the liquid foamed concrete creating a solid mass.
The set time is created by careful selection of the correct materials to suit the application and location. Set times of Propump mix designs are normally between 2 and 8 hours.
The cement types in general use fall into sub categories which are listed below;
1a. Ordinary Portland Cement 52.5N, 42.5N, 32.5N.
Propump mix designs incorporate 200-400kg/m3.
1b. Rapid hardening Portland Cements (RHPC).
Propump mix designs using RHPC incorporate 200-400kg/m3.
1c. Blended Cements using Fine Pulverized Fuel Ash (PFA f ) from coal fired power stations.
Propump mix designs may incorporate up to 70% replacement PFA f.
1d. Blended Cements using Ground Granulated Blastfurnace Slag (GGBS).
Propump mix designs using GGBS should be used with caution as segregation and bubble coalescence can occur.
Propump Foamed concrete is extremely fire resistant and well suited to applications where fire is a risk.
Test have shown that in addition to prolonged fire protection, the application of intense heat, such as a high energy flame held close to the surface, does not cause the concrete to spall or explode as is the case with normal dense weight concrete.
Filler or aggregate
Propump mix designs will only incorporate fine aggregates with a maximum particle size of 5mm (except for light weight aggregates). The aggregate grading should be even with greater than 50% passing a 600µm sieve. Larger aggregate will precipitate causing a poor quality of set material.
Fillers that have been used in Propump mix designs include;
- Marine sand
- Land dug sand
- Crushed concrete
- Crumbed Rubber
- Granite dust
- Limestone fines
- Lytag fines
- Expanded polystyrene
- Coarse Pulverised Fuel Ash (PFA)
Propump foaming agents are used to create a pre-formed foam similar in appearance to a shaving foam. The foam is produced through a specially designed generator using chemicals which have been designed to provide excellent wet concrete stability and outstanding cured properties.
Protein foaming agent designed by Propump for our main contracting arm. Used to provide highly versatile foam for inclusion in mix designs from 200kg/m3 to 1700kg/m3. We are very proud of its performance levels having been used directly by Propump over many years to service its extensive UK and Overseas client base. Suitable for dry foam systems only.
A concentrated version of Propump26, it is used where greater viscosity is required. Propump40 has been used to minimize material loss on voided infill such as mines. Suitable for dry foam system only.
Manufactured to closely duplicate the protein foams. It is extremely active requiring much less energy to create the foam. Used by Propump for heavier density mixes (1200-1700kg/m3). This product can be used for both the dry foam system and the wet foam system.
Foamed concrete characteristics
Foamed concrete is usually a pumpable, free flowing material, it requires no compacting and can be poured in layers of up to 1 metre in depth. Propump place foamed concretes that will search and encapsulate with ease. Foamed Concretes are, to an extent, self-levelling and will freely flow upwards of 30 metres. The characteristics of each different mix design can be modified to suit the application
- Reduced labour / manpower to place
- light weight
- no vibration required
- easily machinable / re-excavatable
Foamed Concrete Capabilities
Foamed Concrete Technical Datasheet
High Density Foamed Concretes
Medium Density Light Weight Foamed Concretes
Low Density Light Weight Foamed Concretes
Ultra Low Density Light Weight Foamed Concretes