Sensitivity of Rheological Properties of Cement Paste with SCC Consistency
Author: Azadehalsadat Asghari
Publisher:
Published: 2018
Total Pages: 201
ISBN-13:
DOWNLOAD EBOOK"Robustness, which is defined as the capacity of a mixture to tolerate small variations in constituent elements, mixing parameters or temperature that are inevitable with production at any significant scale, is a key property to expand the practical implementation of self-consolidating concrete (SCC). At the first step, the effect of different amount of water, amount of superplastizer, mixing time, mixing speed and the addition time of superplastizer on the rheological properties of cement pastes with SCC consistency, has been evaluated. Two different SCC mix design concepts, the powder-type and VMA-type were selected for this research. The results show that the selected powder-type mix design is more robust than the VMA-type to a change in addition time of SP. Then, an experimental study was conducted to evaluate different mix design parameters by varying the binder combination, the type of PCE-SP and the addition of viscosity-modifying agent (VMA) to determine which particular parameters cause the largest difference in rheological behavior due to a variation in adding time of SP. In third step, the robustness of the "loss of workability" of flowable cement pastes, which is mainly affected by variations in the water content and the adding time of the superplasticizer, was evaluated. A comparison study was performed to develop a more accurate vision on robustness of cement paste, and also concrete, by taking into account the time-dependency of the rheological properties. Furthermore, the change in rheological properties of well-dispersed cement pastes subjected to different maximum shear rates has been conducted. It was shown that the choice of maximum shear rate during the rheological measurements is critical for the values of the rheological properties"--Abstract, page iv.
