Viscosity-enhancing admixtures

In the area of tidal concreting for sea defense work, e.g. between tides, the concrete is required to develop strength rapidly even under winter conditions. The advent of viscosity-enhancing admixtures (VEAs) which... 

The ability to consistently produce HFSCC has been made possible by the development of a new type of VEA. Most viscosity-enhancing admixtures (VEA) are readily adsorbed on cement grains and often form bridges between the cement particles. Consequently, they strongly affect... 

Fig. 7.46 Effect of interaction between superplasticizer and viscosity-enhancing admixture on flow value (Yammuro et ai. [73]).

UNDERWATER CONCRETE-COMPATIBILITY PROBLEMS WITH VISCOSITY ENHANCING ADMIXTURES (VEAs)... 

LMC is used in underwater concrete for both new construction and repair. The important requirements to obtain antiwashout capability, such as segregation resistance, flowability, self-leveling characteristics and lower bleeding are provided by the addition of viscosity-enhancing polymeric admixtures at polymer-cement ratios of 0.2-2.0%. These admixtures are water-soluble polymers, and classified under two groups, viz., cellulose types such as methyl cellulose and hydroxy ethyl cellulose and polyacrylamide types such as polyacrylamide and polyacrylamide-sodium acrylate [101]. 

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