Rheological Characteristic of Cement Clean Paste and Flowing Behavior of Fresh Mixing Concrete with Pumping in Pipeline (2007-02)¶

The circumstance of fluid of fresh mixing concrete is analogous to Bingham fluid with pumping pressure in pipeline. The rheological characteristic of fresh mixing concrete along the pipeline wall in the action of push force with high pressure pumping is analysed. The results show that under the action of the concrete for pumping as long as the shear stress τ >τ0 at the position of pipeline wall, the fresh mixing concrete begins to flow, but in an arbitrary radius, the flowing stops before the concrete for pumping to take place. The pull force of concrete for pumping produced by the shear stress is greater than cement paste’s (or cement sand paste ) yield stres τ0′ , the flowing may take place, therefore τ0 >τ0′ , it is advantaged to the fresh mixing concrete for pumping.