The new technology of rheodynamic concrete allows concretes to be obtained that can self compact without vibration, even with densely reinforced structures.
A self-compacting mix should have a high workability and high viscosity.
The fluidity of the mix is guaranteed provided there is no friction between the internal particles and the concrete can flow freely; segregation occurs when the components of the concrete separate out into mortar and large aggregates. Reaching the right balance between fluidity and resistance to segregation – apparently opposing properties – is essential for this type of mix. This balance cannot be achieved when the fluidity of the concrete is obtained by adding only water.
Although a superplasticizer admixture gives high fluidity, alone it does not guarantee the necessary properties to ensure a good degree of self-compacting. That is why GLENIUM STREAM 5 is a complementary admixture when making Rheodynamic Concrete.
Mechanism of Action
GLENIUM STREAM 5 consists of a mixture of water-soluble polymers, which are absorbed onto the surface of the cement granules, thereby changing the viscosity of the water and influencing the rheological properties of the mix.
GLENIUM STREAM 5 has a dual action:
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It resists segregation due to aggregations of the polymer chains when the concrete is not moving.
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It decreases viscosity and maintains internal cohesion of the concrete during casting, thanks to the polymer chains of the admixture, which arrange themselves in the direction of flow of the mix.
The rheological behaviour induced by GLENIUM STREAM 5 is optimised using it in combination with the GLENIUM range of superplasticizers.
GLENIUM STREAM 5 is chloride-free and compatible with all cements envisaged by European and ASTM standard for reinforced concrete. It is incompatible for use with naphthalene sulphonate based superplasticizer admixtures.
Thanks to its particular chemistry with GLENIUM STREAM 5 is it possible to:
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Refine the rheology of the mixes by increasing cohesiveness and eliminating bleeding;
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Produce concretes distinguished by their great stability and strong capacity to retain water;
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Obtain a more even mortar to entrain and keep the solid concrete particles in suspension, thereby ensuring excellent filling of the formwork;
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Make the mixture less sensitive to variations in sand grading, to the shape and moisture content of the aggregates and to the characteristics of the binders;
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Obtain greater flexibility of choice and type of casts because of a low risk of segregation, greater pumping speeds and distances;
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Provide a wide range of tolerance in mix water content, thanks to the viscosing effect, without problems of segregation.