Research Progress of Rheology Parameters Characterizing Workability of Wet-mix Shotcrete
In order to increase the role of workability to guide the construction performance(transportability and shootability)of wet-mix shotcrete,the requirements for workability in national technical specifications were summarized.The research progress on the correlation between rheological properties and shootability was reviewed.The time-varying mechanism of rheological properties was discussed.The current prediction models of time-depended variable rheological properties were summarized.The results show that slump could not solve the technical contradiction between transporta-bility and shootability,and rheological parameters were more useful than slump.The yield shear stress increased,the build-up thickness increased,and the rebound rate decreased.The plastic viscosity decreased,the pipeline transportation pressure decreased,which resulted in that the transportability improved.However,the correlation between yield shear stress and compactness,or plastic viscosity and compactness,still needed further research.The time-varying models of rheological properties were mostly empirical formulas such as exponential,logarithmic,linear,and power function.Therefore,the prediction models should be deduced considering more physical significance.The time-varying prediction models lacked effective verification methods,and the focus should be on developing in-situ evaluation methods for the rheological properties of wet-mix shotcrete under rapid setting systems.
NETL
NSTL
万方数据
