Measuring Method Online on Rheological Parameters of Fresh Concrete

In order to investigate workability of fresh concrete quantitatively, a newly device for test online was invented to measure rheolgical parameters of concrete. The device consists of temperature measurement system, torque measurement system, driving system and human-computer interaction system. The working principle of this device is to adopt single-chip microcomputer auto-control system driving cross axis torquemeter operation by stepping motor and, total 6 classes different speeds of the corresponding rotating torque are obtained to calculate the rheological parameters of fresh concrete. Results of verifying test continuously with the device indicated that rheological characteristic of fresh concrete is similar to Bingham models and yield stress reduces linearly with increase of slumps, but relation between plastic viscosity and slumps is inexplicit. The device can be used to measure continuous rheological parameters for situ-pouring concrete expediently.