Yield stress of cement grouts
(English)Manuscript (preprint) (Other academic)
: The rheology of cement grout is complex due to its thixotropic nature and the presence of a yield stress. Despite the importance of the yield stress for grouting design, no standard methods are yet available to determine the yield stress. Most common methods are based on using conventional rheometers, but the results are subjective due to the measurement techniques, applied shear history and hydration. In this work, measurement of the yield stress of cement grout was performed with different measurement techniques using a conventional rheometer. In addition, in-line measurements using an ultrasound based technique were made in order to visualize the flow profile and perform a direct measurement of the yield stress. Two ranges of yield stress, static and dynamic yield stress, were measured. These results should be used for design purposes depending on the prevailing shear rate. The ultrasound based Flow Viz industrial rheometer was found capable of performing direct in-line measurement of the yield stress and providing a detailed visualization of the velocity profile of cement grout.
yield stress, thixotropy, grouting, cement grout, in-line rheology, UVP+PD, ultrasound velocity profiling
Research subject Civil and Architectural Engineering
IdentifiersURN: urn:nbn:se:kth:diva-176886OAI: oai:DiVA.org:kth-176886DiVA: diva2:868710
The authors wish to acknowledge the financial support from the Swedish Rock Engineering Research Foundation (BeFo) and the Swedish Construction Industry Development Fund (SBUF).
QS 20152015-11-112015-11-112015-11-12Bibliographically approved