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Utest Material Testing Equipment

RoadReader Nuclear Density Gauges

Product Code

RoadReader Nuclear Density Gauges Model 3430
RoadReader Nuclear Density Gauges Model 3440

Standards

ASTM D 2922, D 3017, D 2950, C 1040

The Troxler RoadReader nuclear moisture / density gauges are used by many contractors, engineers and highway departments for compaction control of soil, aggregate, concrete and full asphalt. The ASTM standarts numbers D 2922, D 3017, D 2950 and C 1040 are met or exceeded by these gauges. Two test models are avaliable for density determination: Direct transmission and Backscatter. The operator selects the mode depending on the material type and thickness of the layer being tested. The model 3430 is avaliable with keypad, display and operator’s manual in languages and is the siplest most economical gauge offered by Troxler. The Model 3440 provides 30 special functions, storage of up to 450 test records, an 18-month warranty and many more options that make it simple to operate and a necessity for all technicians.

Three Test Modes

BACKSCATTER

Backscatter is rapid and nondestructive. The gamma source and detectors remain inside the gauge which rests on the surface of the test material. Gamma rays enter the test material and those scattered through the material and reaching the detectors are counted. Backscatter is primarily used to determine density on layers of asphalt and concrete approximately 4" thick.

DIRECT TRANSMISSION

The gamma source is positioned at a specific depth within the test material by insertion into an access hole. Gamma rays are transmitted through the test material to detectors located within the gauge. The average density between the gamma source and the detectors is then determined. Erros resulting from surface roughness and chemical composition of the test material are greatly reduced and aguge accuracy is improved. Direct transmission is used for testing lifts of soil, aggreaget, asphalts and concrete up to 12" depth.

MOISTURE DETECTION

The moisture measurement is nondestructive with the neutron source and detector located inside the gauge just above the surface of the test material. Fast neutrons enter the test material and are slowed after colliding with the hydrogen atoms present. The helium 3 detector in the gauge counts the number of thermalized (slowed) neutrons which relates directly to the amount of moisture in the sample.

Both Models Offer

  • Direct readout of wet density, dry density, moisture, %moisture, %voids and %compaction.
  • Lightweight
  • Powered by rechargeable nicad batteries or backup alkaline batteries
  • Prompts user through steps of operation
  • Software allows for moisture, density and trench offsets
3430 Features
  • Choice of languages-keypad, display and operator manual available in English, Chinese, Spanish and French.
  • Simple to Operate-single keystroke function access. Direct readout of test results.
3440 Features
  • Data storage- stores up to 450 complete test records which canbe downloaded to a printer or  computer.
  • Extended storage-gauge allows notes to be stored with test record.
  • Automatic indexing-eliminates a major source of operator error by automatically sensing depth of measurement.
  • 30 special functions provided-self test and service programs, selected precision and field calibration for special materials.
  • Calculator mode with storage.
  • Nomograph method for measurement of asphalt overlays.

Measurement (U.S. Customary Units)

Direct Transmission Density (6")

15 sec.

1 min.

4 min.

Precision at 120 pcf

±0.42 pcf

±0.21 pcf

±0.11 pcf

Composition error at 120 pcf

±1.25 pcf

±1.25 pcf

±1.25 pcf

Surface error (0.05", 100% Void)

-1.1 pcf

-1.1 pcf

-1.1 pcf

Backscatter (98%) (4")

15 sec.

1 min.

4 min.

Precision at 120 pcf

±1.00 pcf

±0.50 pcf

±0.25 pcf

Composition error at 120 pcf

±2.50 pcf

±2.50 pcf

±2.50 pcf

Surface error (0.05", 100% Void)

-4.7 pcf

-4.7 pcf

-4.7 pcf

Moisture at 15 pcf

15 sec.

1 min.

4 min.

Precision at 15 pcf

±0.64 pcf

±0.32 pcf

±0.16 pcf

Surface error (0.05", 100% Void) Depth of measurement

@ 15 pcf (8.45")

 

-1.12 pcf

 

-1.12 pcf

 

-1.12 pcf

 

Measurement (S.I.  Units)

Direct Transmission Density-150mm

15 sec.

1 min.

4 min.

Precision at 2000 kg/m3

±6.8 kg/m3

±3.4 kg/m3

±1.7 kg/m3

Composition error at 2000 kg/m3

±20.0 kg/m3

±20.0 kg/m3

±20.0 kg/m3

Surface error (1.25mm, 100% Void)

-17.0 kg/m3

-17.0 kg/m3

-17.0 kg/m3

Backscatter (98%) (100mm)

15 sec.

1 min.

4 min.

Precision at 2000 kg/m3

±16.0 kg/m3

±8.0 kg/m3

±4.0 kg/m3

Composition error at 2000 kg/m3

±40.0 kg/m3

±40.0 kg/m3

±40.0 kg/m3

Surface error (1.25mm, 100% Void)

-75.0 kg/m3

-75.0 kg/m3

-75.0 kg/m3

Moisture

15 sec.

1 min.

4 min.

Precision at 250 kg/m3

±10.3 kg/m3

±5.1 kg/m3

±2.6 kg/m3

Surface error (1.25mm, 100% Void)

Meas. Depth @ 250 kg/m3 - 212.5mm

-18.0 kg/m3

-18.0 kg/m3

-18.0 kg/m3

Calibration

Accuracy of Density Standards

±0.2%

Accuracy of Moisture Standards

±2.0%

Calibration Range

70-170 pcf (1100-2700 kg/m3 ) Density

0-40 pcf (0-640 kg/m3 ) Moisture

Radiological

Gamma Source

8 mCi ±10% Cs-137

Neutron Source

0.060 mCi ±10% Cf-252 or

40 mCi ±10% Am-241:Be

Source Housing

Stainless Steel Encapsulation

Shielding

Tungsten, lead and cadmium

Surface Dose Rates

20.5 mrem/hr max., neutron and gamma

Source Rod Material

Stainless Steel

Shipping Case

DOT 7A, Type A

             

Mechanical

Case

High Impact Plastic   29.5 L x 14 W x 17 T in.

Vibration Test

0.1 in. (2.5 mm) @ 12.5 hz

Drop Test

300 mm on 25 mm diameter steel ball

Operating Temp:

Ambient: 14 to 158°F (-10 to 70°C) Surface: 350°F (175°C)

Storage Temp.

-70 to 185°F (-55 to 85°C)

Gauge Size (no handles)

14.8 x 9.1 x 7.2 in. (376 x 231 x 183 mm)

Gauge Height (with handles)

12": 23.25 in. (591 mm)  8": 19.25 in. (489 mm)

Weight

29 lbs. (13.2 kg)

Shipping Weight

90 lbs. (40.8 kgs) w/case

Available Models

8" or 12" index rod with 1" or 2" increments

(200 or 300 mm index rod with 25 or

50 mm increments)

Electrical

Time Accuracy and Stability

0.005%, 0.0002% / °C

Power Supply Stability

0.01% / °C

Stored Power

30 watt hours

Battery Recharge Time

14-16 hours (automatic cutoff)

Charger

110/220 V ac, 50-60 Hz or 12-14 V dc

Readout

2 x 16 alpha-numeric liquid crystal display

Notes

Gauge returns to Gauge Ready (power saving mode) after two minutes of inactivity, except in standard, stat test, drift test, and in nomograph programs

when a 30-minute delay is provided. After 5 hours of inactivity, gauge performs complete power shut-down.

 

Battery packs are fully protected against overcharge and overdischarge. Emergency Use - Capable of operation with D size alkaline batteries.