## 5 Werkstofftechnik

### Filtern

#### Dokumenttyp

- Buchkapitel (2) (entfernen)

#### Schlagworte

- Concrete (2)
- Rheology (2)
- Aggregates (1)
- Cement (1)
- Flow Coefficient (1)
- Flow coefficient (1)
- Limestone Filler (1)
- Particle Size Distribution (1)
- Particle size distribution (1)
- Reference Material (1)

#### Organisationseinheit der BAM

- 7 Bauwerkssicherheit (2) (entfernen)

In order to observe the effect of the aggregate phases between 2 mm and 16 mm without overlap with rheological effects induced by the cement hydra-tion and without interactions with a threshold fine sand particle size that affects both, paste and aggregates, rheological experiments were conducted on a lime-stone filler based paste mixed with aggregates up to 16 mm. Various aggregate fractions were blended and mixed with the replacement paste in different vol-umetric ratios.
The dry aggregates’ flow coefficients were determined and compared to yield stress and plastic viscosity values at different aggregate volume fractions. The results indicated that the flow coefficient is not a suitable parameter to predict the performance of the aggregates in the paste. It was shown that the yield stress of pastes is largely determined by the blend of different aggregate frac-tions, while the plastic viscosity to large extend depends upon the coarsest ag-gregate fraction.
Based on the results, ideal aggregate composition ranges for minimised yield stress are presented. For the plastic viscosity no such grading curves to achieve minimum values could be found, but high viscosity curves are identified.

In order to observe the effect of the aggregate phases between 2 mm and 16 mm without overlap with rheological effects induced by the cement hy-dration and without interactions with a threshold fine sand particle size that affects both, paste and aggregates, rheological experiments were conducted on a limestone filler based paste mixed with aggregates up to 16 mm. Vari-ous aggregate fractions were blended and mixed with the replacement paste in different volumetric ratios.
The dry aggregates’ flow coefficients were determined and compared to yield stress and plastic viscosity values at different aggregate volume fractions. The results indicated that the flow coefficient is not a suitable parameter to predict the performance of the aggregates in the paste. It was shown that the yield stress of pastes is largely determined by the blend of different aggregate fractions, while the plastic viscosity to large extend depends upon the coars-est aggregate fraction.
Based on the results, ideal aggregate composition ranges for minimised yield stress are presented. For the plastic viscosity no such grading curves to achieve minimum values could be found, but high viscosity curves are identified.