Structuro PSN is a chloride-free superplasticising additive based on selected polycarboxylic based polymers. It is supplied as an off-white powder that disperses instantly in water.

Structuro PSN disperses the fine particles in the mix, enabling the water content of the concrete to work more effectively.

Uses

• For the manufacture of self-levelling or highly flowable mortars.
• To provide early strength acceleration and further strength increase at all ages by significantly reducing the water in the concrete or mortar mix.
• Particularly suitable for precast concrete and others requiring high early strengths.
• To significantly improve the workability of site-mixed mortar and concrete without increasing water demand.
• To provide increased durability by increasing the ultimate strengths and reducing the permeability of concrete and mortars.

Advantages

• Increases early age strengths without increasing cement contents.
• Enables further reductions in the water/cement ratio, allowing the production of high strength concrete and mortar without excessive cement content.
• Its use in the production of flowable concrete allows for easier construction, faster placement and compaction and reduced labour costs without increasing water content.
• Improved cohesion and particle dispersion minimises segregation and exudation and improves pumpability of concrete and mortar.

Standards

Structuro PSN complies with UNE-EN 934-3:2004 as an air-entraining / plasticising agent.

Typical dosage

The optimum dosage of Structuro PSN to achieve specific requirements should be determined by testing, using the materials and conditions that will be used in practice. This allows optimisation of the admixture dosage and mix, as well as a complete evaluation of the concrete.

Typical dosages range from 0.3 to 3.0 kg/100 kg of cement.

Properties

The following results were obtained at a temperature of 20ºC:

• Appearance: White powder
• Density: 0,87 g/cm3 at 20 ºC
• Chloride content: Free
• Air occlusion: Normally less than 2% additional air occlusion at normal dosages.
• Alkali content: Less than 72 g Na2O equivalent/litre of additive

Mode of use

Mix design

When the intention is to improve strengths, initial trials should be made with normal concrete or mortar mixes. The addition of admixture allows water to be removed from the mix while maintaining workability at levels obtained prior to the use of admixture. After initial trials, minimal modifications should be made to the overall mix design to optimise results.

When the primary intention is to provide high workability concrete, the initial mix design should be that of pumped concrete. Fosroc Euco's Technical Department will advise on the appropriate mix to achieve free-flowing concrete.

In a correct fluid concrete mix, the better dispersion of the cement particles and the more efficient use of the mixing water will improve the cohesion of the mix. The slight air occlusion obtained with Structuro PSN will help to minimise exudation and segregation. After initial trials, minimal modifications should be made to the mix to optimise results.

Compatibility

Structuro PSN is compatible with other Fosroc Euco admixtures used in the same mix. If more than one admixture is used, they should be added separately and not mixed together prior to addition. The resulting properties of concrete or mortar containing more than one admixture must be checked by prior testing. Structuro PSN is suitable for use with all cements complying with RC-08.

Dosing system

he correct amount of Structuro PSN should be measured out using a suitable dosing system. Normally the admixture is added together with the sand and cement in the ready-mix to achieve a perfect homogenisation of the admixture within the concrete or mortar mass. When a high workability concrete or mortar is required from a normal workability concrete, Structuro PSN admixture can be added directly to the truck mixer. To ensure complete mixing of the admixture in the truck mixer, a mixing time of at least 2 minutes at high speed is required. Contact the Fosroc Euco Technical Department for advice on suitable equipment and installation.

Effects of overdosage

An overdosage of twice the maximum dosage indicated may cause additional air locking.

Curing

As with all cementitious systems, adequate curing of the mortar should be sought to ensure that no cracking or hairline cracks result. Fosroc Euco Concure, water (sprayed) or wet burlap can be used as a curing membrane. 

Clean up

Spills of Structuro PSN should be absorbed with sand or earth and transferred to suitable containers. Product residues should be flushed away with a large amount of water. Disposal of the product and packaging is the responsibility of the end user.

Storage

Structuro PSN has a storage life of 12 months, if kept in a dry place and in its original, closed containers at a temperature between 2ºC and 40ºC.

Precautions

Safety and hygiene

Structuro PSN has a low level of toxicity. Avoid contact with skin and eyes, or inhalation of dust. Wear suitable protective clothing, gloves, eye/face protection and mask.

If skin contact has occurred, wash with plenty of clean water. In case of contact with eyes, rinse immediately with plenty of clean water and seek medical attention. In case of accidental ingestion, seek immediate medical attention. Do not induce vomiting.

For further information, please refer to the Material Safety Data Sheet.