Construction Aid Monitors Compaction
The Electrical Density Gauge (EDG) is a non-nuclear alternative for nuclear gauges in determining the physical properties of compacted soils used in road beds and foundations. The EDG is a portable, battery-powered instrument capable of being used anywhere in the world without the problems associated with nuclear safety.
The EDG measures and displays the wet and dry density, gravimetric moisture content and percent compaction. Easy-to-use, the EDG can be used as a construction aid to monitor day-to-day compaction operations by providing performance and measurement results highly comparable to those achieved with traditional methods, including nuclear gauge, sand-cone and oven drying methods.
The EDG's accuracy is achieved using point-to-point radio frequency, measuring directly between electrodes driven into the soil, ensuring positive measurements through the soil at full depth of electrodes.
No need to make sure the soil is homogeneous or to rely on radio frequency "waves )31 to penetrate soil materials from the surface. For the contractor the advantages of using the EDG is that it does not require a highly trained or licensed technician, is easy to learn which enables anyone to be trained and is simple to use that measurements are fast and can be done at greater intervals for a more thorough evaluation.
Principles of Operation
The EDG measures the electrical dielectric properties of compacted soil materials and its moisture using high radio frequency between sets of electrodes. The measured dielectric properties are compared to a "Soil Model" which is a soil-type specific calibration with a captured set of premeasured and unique dielectric properties representing sets of density and moisture content values. At the end of a field measurement, an algorithm determines the wet and dry density, gravimetric moisture content and percent compaction values. Additional accuracy comes by the way of the attached temperature probe.
In the field, four tapered electrodes or darts are driven into the ground by a hammer in a cross pattern using the template. Between the two sets of two tapered darts, four point-to-point electrical measurements are made and the electrical characteristics averaged. The representative density and moisture content are displayed in choice of metric SI or English inch-pound units. The tapered dart's depth of penetration positively regulates the depth of measure. In addition, the dart's taper continually ensures the positive contact of the soil with every impact of the hammer.
The length of the tapered darts positively determines the depth of measure-different lengths are available. The use of the EDG is simplified via a display with menu-driven step-by-step instructions and measurement results can be saved.
Alternative to the sand-cone and oven drying methods and Nuclear Moisture- Density Gauges-No sources!
- No licensed technician required
- Easy to learn and simple to use
- Uses reliable and well established point-to-point RF technology
- Accurate, robust and lightweight
- Measurement results in two to three minutes
Density, moisture and acceptance testing of compacted materials for:
- Embankments and fills
- Roadway subgrades, subbases and bases
- Utility backfills and trenches
- All construction soils
ASTM Standard in process, D-18 Committee
H-4114 — Electrical Density Gauge Includes
Console; 4-tapered electrodes; hammer; soil sensor and cables; template, temperature probe and battery charger.
|Wet Density Range||typical compacted earth sites range|
|Dry Density Accuracy||within 3% of standard tests|
|Moisture Content Range||typical compacted earth sites range|
|Moisture Content Temperature||0-50°C|
|Ambient Operating Humidity||5-90% non-comdensing|
|Power||Rechargeable 12V lead acid gel cell 4.0 Ah|
|Battery Life||Approx. 8 hrs. with full charge|
|Dimensions||Console: 13.5" x 12" x 6"
(343 mm x 305 mm x 152 mm)
|Net Weight||Console: 11 lbs. (5 kg)
Accessories: 4 lbs. (1.8 kg)
|Specifications may change without notice|
|U.S. Patent # 6,380,745, other patent pending|