High-strength and ultra-high performance concretes

Improvement of the rheological behavior

At present, high-strength and ultra-high performance concretes gain more and more in importance across the world. They are characterized by an optimized packing of the particles as well as by extremely low water/cement ratios of < 0.25. The addition of polycarboxylate superplasticizers to concretes with such low water content at best results in very sticky, creeping concretes and often the PCEs even fail completely.

It will be shown in the lecture that a combination of common PCE superplasticizers and simple, non-ionic molecules achieves concretes with very good flow characteristics at...

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