Modified Formula for Designing Ultra-High-Performance Concrete with Experimental Verification

Jarosław Siwiński1, Anna Szcześniak1, Adam Stolarski1

  • 1Faculty of Civil Engineering and Geodesy, Military University of Technology, 2 gen. Sylwestra Kaliskiego Street, 00-908 Warsaw, Poland.

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Strength of Cement

Strength tests for cement are not performed directly on neat cement paste due to difficulty in obtaining consistent, reliable specimens. Instead, cement is typically tested in the form of cement-sand mortar.
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Testing Water Quality01:14

Testing Water Quality

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Accelerators01:17

Accelerators

Accelerators in concrete serve as admixtures to speed up the hardening process, enabling the concrete to achieve early strength faster. Although accelerators do not necessarily impact the time it takes concrete to set, they reduce this time in practice. A common accelerator is calcium chloride, which is particularly useful for hastening early strength development in cold weather or for rapid repair jobs that require quick heat generation after mixing.
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Superplasticizers01:30

Superplasticizers

Superplasticizers are advanced admixtures that enhance the workability of concrete by lowering the water content without compromising the strength of the material. These substances are highly effective water reducers, improving concrete flow, making it easier to work with, and enabling concrete to reach inaccessible areas or densely reinforced sections without mechanical vibration. The key components in superplasticizers are either sulfonated melamine or naphthalene formaldehyde condensates,...
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