Rheological Characteristics of Power-law Cement Grouts Based on Time-dependent Behavior of Viscosity

Grouting technology is playing an increasingly important role in engineering construction, but the theoretical research lags behind the engineering practice of the grouting technology in need. At present, the research on the laws of the grouts rheological properties and grout diffusion are important contents of scientific research workers. This paper researches grouts time-dependent behavior of viscosity, and verifies the engineering commonly used water-cement ratio (W/C) 0.5, 0.6, 0.7 cement grout obey the power-law fluid properties. Different water cement ratio grouts viscosity increases with the increase of gelation time. Experimental results show that quantitative relationship between W/C and consistency coefficient and apparent viscosity of power-law cement grouts may be all expressed by exponential function of taking e as base number, in addition their fitting effect are very good. The theoretical values of these parameters calculated by quantitative relationship are greater than those of actual measurement values in the verification experiments, moreover their difference are all distributed in the range 5%. Both consistency coefficient and apparent viscosity of power-law cement grouts have rapidly increased over time, but rheological index is little variation over time. So the consistency coefficient and apparent viscosity belong to time-dependent rheological parameters. Considering the time-dependent behavior of power-law grouts, its rheological equation can be expressed as tau=c(0)e(kt)gamma(n), and these research results could provide reasonable scientific guidance to practical engineering.