Instead of using one single-point test to measure workability, multiple single-point tests can be performed. For instance, ACI 309.1R-93 describes the use of four tests namely, for harshness, segregation resistance, shear resistance, and stickiness to better characterize workability. Each test is considered at least partially independent of the other tests. Harshness is measured as the spread of concrete on a flow table; segregation resistance is measured as the amount of mortar separated from concrete by jolting a flow table; shear resistance is measured using the shear box developed by Terzaghi and Casagrande for soils; and stickiness is measured as the vertical force required separating a steel plate from concrete.
Advantages:
The four tests give more information about a given concrete mix than one single-point test.
Each test is simple and inexpensive to perform.
Disadvantages:
Conducting multiple tests requires additional time and cost.
The tests do not directly measure yield stress and plastic viscosity.
