STRUX® 90/40

Product Description

STRUX® 90/40 is a unique, high strength, high modulus synthetic macro fibre reinforcement that is added to ready-mix and precast concrete at the batching stage. STRUX® 90/40 controls drying shrinkage cracking, so can be used as an alternative to steel fabric and steel fibre reinforcement

Benefits & Advantages

• Controls drying shrinkage cracking by controlling the propagation of micro-cracking - improves toughness and durability of concrete.
• Can be used as an alternative to steel fabric reinforcement and steel fibre reinforcement.
• Uniformly distributed throughout the concrete matrix - no risk of incorrect steel fabric reinforcement placement.
• Improves residual flexural strength, impact and fatigue resistance of concrete - Re,3 values in excess of 30% can be reliably achieved (see Concrete Society Technical Report 34, 3rd Edition).
• Removes a site process so saves time on construction programme.
• No steel fabric storage, movement or crane costs.
• No risk of injuries from moving and installing steel fabric reinforcement.
• Ready-mix concrete truck can back up and freely discharge concrete, could remove/ reduce pumping costs.

Applications

• Ground bearing floor slabs
• External pavements
• Composite steel deck flooring
• Precast concrete

Note: STRUX® 90/40 is not intended as a substitute for steel reinforcement in any application other than those listed. Always consult relevant national and European codes.

Addition Rates

STRUX® 90/40 addition rates are dependent on the specific application. Addition rates are also dependant on the desired hardened concrete properties and will vary between 2.3 to 7.0 kg/m³. Please see STRUX® 90/40 engineering bulletin for detailed information.

+ = positive effect         (1) Only if positioned in top third of floor slab

– = no effect                  (2) Only if positioned in bottom third of floor slab

Mix Design and Mixing Requirements

STRUX® 90/40 may require the use of a superplasticiser such as ADVA® to achieve the required workability. In addition, slight increases in fine aggregate contents may be needed.

At dry batch ready-mix plants, add the STRUX® 90/40 bags to the truck before the concrete constituents. STRUX® 90/40 bags are water degradable and will degrade when wetted. At wet batch ready-mix plants, add the STRUX® 90/40 bags to the truck before the concrete constituents.

Add the first batch of concrete constituents to the truck SEMIDRY. This will break up the STRUX® 90/40 bags and evenly disperse the fibres. Remember to make up the water content on subsequent batches. After fibre addition, the concrete must be mixed in a drum at the recommended mixing speed for a minimum of 70 revolutions to ensure adequate dispersion. Please contact GCP for further information.

Compatibility

STRUX® 90/40 is compatible with all GCP admixtures. The action of STRUX® 90/40 in concrete is mechanical and will not affect the hydration process of the cement. Each liquid admixture should be added separately to the concrete mix.

Packaging

STRUX® 90/40 is available in 2.3 kg concrete-ready bags.

Technical Data

Effect of STRUX® 90/40 Dosage on Residual Strength

^{Note: These curves are based on averages of several beam tests. The toughness performance will depend on the concrete mix design used.}

^{Note: These figures (fe,3 and Re,3) are indicative of the performance of concrete mixes containing STRUX® 90/40 but they will vary depending on the hardened properties of the concrete. It is reasonable to expect higher figures when tested in other concrete mixes.}

^{Note: The addition of STRUX® 90/40 fibres, to control plastic shrinkage cracking, does not negate the need for appropriate and efficient curing techniques}