21 Sep

Concrete Additions Explained

Concrete Additions Explained

Additives to concrete change the composition of the mix.

Polypropylene Fibres are made up of thousands of individual fibres which when added to the mixing process are dispersed evenly and provide additional benefits to concrete.

12mm fibres are used to control plastic shrinkage and settlement cracking and will also provide secondary reinforcement in all concrete applications.

Benefits in Concrete
Improves mix cohesion
Controls Plastic Shrinkage
Reduce Freeze Thaw effects
Improves structural strength
Reduce steel reinforcements, although not a replacement
Reduce crack widths and control widths tightly, Improving durability
Reduce Shrinkage
Improved Fire resistance.

54mm fibres when added to concrete will significantly improve its durability and residual strength.

Benefits in Concrete
All the benefits listed above
Increased Impact resistance
Increased tensile strength
Improved resistance to spalling and edge damage
Plastic Shrinkage crack reduction
Fire resistance
Improved residual strength
Potential to reduce section thickness
Non-corrosive and non-rusting

Chemical admixtures involve adding chemical products to concrete with the effect of improving the performance and engineering the correct characteristics into the concrete. Addition of plasticizers make the concrete more fluid permitting it to be placed where  reinforcing considerations has made it awkward to achieve  a good fill, or where other difficulties require a wetter concrete mix which is easier to use. Water reducing mixes limit the amount of water necessary and improve the workability of the concrete without loss of strength. Shrinkage reducing concrete admixes are also available which reduce the necessity for undesirable construction and expansion joints.

Retarders are available to slow down the setting time of the concrete for extended time to level and tamper the concrete.

‘Slump’ – is a measure of what the concrete’s ‘plastic (fluid)’ condition will be when the concrete is placed. The higher the slum the easier the concrete flows. To achieve best performance, design concrete mixtures commonly state a ‘slump range’. However adding, (for example) excessive water to the concrete mix, can although making it easier to pour out, seriously weaken the strength of the concrete, however the same flow can be achieved by adding the right amount of admixture and thereby maintain the original design strength.

PLEASE DO NOT HESITATE TO CALL US TO LET US HELP YOU CHOOSE THE RIGHT MIX FOR YOUR APPLICATION