Verifi Concrete Quality Blog

Posts Tagged ‘slump meter’

Automated Slump Meter vs. Hydraulic Pressure Meter

by Verifi

Most ready mix concrete trucks come equipped with a so-called “slump meter” or “slump gauge”, as shown in the below photo. These devices are nothing more than a dial gauge indicating the hydraulic pressure to rotate the drum. Hydraulic pressure alone is insufficient to determine slump. Therefore, these devices are not true slump meters.

Hydraulic pressure gauge

In contrast, Verifi uses additional sensors and advanced software to calculate and display slump. Verifi readings of slump are accurate to within +/- 1 in (25 mm) of the manual slump test. Verifi shows slump, not hydraulic pressure.

verifi automated slump meter

© Verifi LLC

Verifi is a true concrete slump meter because:

  1. Sensors measure drum speed for use in calculating slump. Increased drum speed results in increased hydraulic pressure.
  2. Verifi uses two hydraulic pressure sensors to compensate for the hydraulic pressure needed to operate the drum in the discharge direction.
  3. Verifi obtains load size from the batch software and calculates changes in load size during discharge. Increased load size results in increased hydraulic pressure.
  4. Software algorithms use advanced filtering to remove noise.
  5. Verifi obtains the mix design from the batch software. Although most mixes use the same Verifi slump calibration for a given truck mixer type, Verifi can use a different calibration for specialty mix designs.
  6. Verifi field service engineers calibrate each truck mixer type to ensure accurate slump readings.
  7. Slump readings are available in real time anywhere with an internet connection, which enables ready mix producers to ensure concrete stays in specification.

In addition, Verifi equipment on the truck adds water and admixture automatically to reach the target slump.