The density requirement for the material to be compacted is predetermined by the engineers in the soil laboratory. From
these lab tests a given density standard for this material will result. Field tests will insure compaction to this standard.
For trouble shooting, refer to pages 11
The normal method of operation is in a "back and forth" pattern. On short runs, the shuttle method is used without turning
around. On long passes, the turn-around method may be used.
Field testing the compacted area will determine the number of passes and selection of frequency required.
The frequency range is listed below. Always compact in low range - 0 to 5 MPH. High range, approximately 12 to 16
MPH, is used for travel only to a different site over smooth surfaces. Always stop machine and set parking brake before
changing transmission speed range because hydrodynamic braking is inoperative when transmission is in neutral. NOTE:
For ease of shifting, jog travel lever, with engine at low idle.
For the first passes, use lower frequency - 1200-1500 vibrations per minute. For "tender" type soils or weak foundations,
use lower frequency also - 1200-1300 vibrations per minute on first passes.
Frequency (VPM) can be read on the Vibration Frequency Gauge affixed to the instrument panel. To change frequency,
move the Vibration Control Lever. The further the lever is moved away from "neutral", the higher the frequency, either
forward or reverse travel.
REX VIBRATION METER
The vibration meter measures the amplitude of roll vibration and this amplitude is indicated on the Vibration Meter
Gauge. The higher the meter reading, the greater the amplitude. Popular theory indicates that the maximum amplitude
occurs at or near the point of soil resonance; and at this point of soil resonance, compaction is most efficient.
Soil resonant frequency can vary with the type of soil, inherent soil moisture, and degree of compaction. Thus the soil
resonant frequency can change with successive passes of the compactor.
To utilize the Rex vibration meter, the operator adjusts the frequency at the beginning of the pass to maximum amplitude
by reading the highest meter indication. This will serve as a guide to obtain the most efficient operation. The vibration
meter is especially valuable as a guide where high densities are difficult to obtain.
*FREQUENCY RANGES
SP848 ...................................... 1200-1800 VPM
CAUTION
REXNORD assumes no liability for any damage due to vibrations transmitted by REX Vibratory Rollers.
This is an area that is unpredictable unless all soil and subsoil conditions are known. The manufacturer of this equipment
can only alert the equipment operator that good judgment has to be exercised when compacting close to structures. Any
vibration propagation may have to be checked before proceeding.
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