What is a Troxler

The Troxler Model 3440 Roadreader™ nuclear moisture/density gauge offers two test modes for measuring the density of soil, aggregate, concrete and asphalt materials. The direct transmission mode allows the source to be lowered below the surface in order to test a larger area of material and improve gauge precision.

What is a Troxler test?

The Troxler Model 3440 Roadreader™ nuclear moisture/density gauge offers two test modes for measuring the density of soil, aggregate, concrete and asphalt materials. The direct transmission mode allows the source to be lowered below the surface in order to test a larger area of material and improve gauge precision.

How does a nuclear Densometer work?

In geotechnical engineering, a nuclear densometer or soil density gauge is a field instrument used to determine the density of a compacted material. The device uses the interaction of gamma radiation with matter to measure density, either through direct transmission or the “backscatter” method.

What is a Troxler gauge?

The Troxler nuclear moisture density gauges are used by many contractors, engineers, and highway departments for compaction control of soil aggregate, concrete, and full depth asphalt. The gauges meet or exceed the ASTM standards D6938, D2950, and C1040. … The owner can customize the gauge to meet their testing needs.

How do you do a soil compaction test?

Obtain layered soil sample (via our VTK Soil Sampler if equipped)
Determine the weight of the Proctor mold with the base and the collar extension.
Assemble the compaction tool.
Place soil in the mold in 3 layers.
Compact the soil with 25 well-distributed blows of the hammer.

What is ASTM D6938?

ASTM D6938 This test method describes the procedures for measuring in-place density and moisture of soil and soil-aggregate by use of nuclear equipment. The density of the material may be measured by direct transmission, backscatter, or backscatter/air-gap ratio methods.

How do you perform a nuclear gauge leak test?

All radioactive licenses issued by regulatory agencies have a requirement for you to perform a leak or wipe test on your gauges. This test typically takes less than 5 minutes per gauge and it usually involves wiping a small piece of filter paper across areas near the locations of the sources in the gauge.

Who invented the nuclear density gauge?

In the late 1950s, North Carolina State University School of Agriculture asked electrical engineer William F.Troxler to design a portable nuclear gauge to measure the water content of soils in the field to help farmers stimulate plant growth.

Are nuclear density gauges safe?

Nuclear gauges use radioactive sources to identify the thickness, density or make up of a wide variety of material or surfaces. These gauges, which are safe to use when the proper safety measures are followed, help people build safe buildings, roads, and make reliable products.

What is field wet density?

Relative compaction – The percentage ratio between the field density of a soil to the maximum density as determined by standard or modified compaction. Wet density – Mass bulk soil, including solid particles, water and air contained in a unit volume.

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Which of the following force is associated to radioactive decay?

weak interaction, also called weak force or weak nuclear force, a fundamental force of nature that underlies some forms of radioactivity, governs the decay of unstable subatomic particles such as mesons, and initiates the nuclear fusion reaction that fuels the Sun.

What are the two types of radioactive material used in the gauge?

Gamma, beta and neutron radiation sources can all be used in nuclear gauges, depending on the application. Neutron radiation is very penetrating and is scattered by materials with a high hydrogen content, e.g. water. It is frequently used for measuring the moisture content in soil and asphalt.

Can you use a nuclear density gauge in the rain?

Do not use the gauge in the rain. If it gets wet dry it immediately. If needed, open the keypad and allow air to flow through.

What is the density of nuclear matter?

Nuclear substance possessing this mass density is called nuclear matter, and its mass density, called nuclear density, is found to be 2.8 × 1014 g/cm3.

What is C soil?

Type C Soils are cohesive soils with an unconfined compressive strength of 0.5 tsf (48 kPa) or less. Other Type C soils include granular soils such as gravel, sand and loamy sand, submerged soil, soil from which water is freely seeping, and submerged rock that is not stable.

What is sand cone method?

A sand-cone method is commonly used to determine the density of compacted soils. … Sands with different particle size distributions are used in the testing to examine how sand grain size influences the determination of density in the field.

Why do we use sand replacement?

9.3. The sand replacement method is used to determine in-place density. The sand replacement method of determination of in situ density uses a sand-pouring cylinder, cylindrical calibrating container, tray with a central circular hole, and a chisel. … The first step involves calibration of a sand-pouring cylinder.

What is a radiation leak test?

A leak test of sealed sources must be performed every six months. A sealed source is a contained source that has been constructed and tested to pass specific accident conditions without the release of radioactive material. … The leak test must be done in accordance with the manufacturer’s instructions.

How frequently do sealed radioactive sources need to be leak tested?

(1) Each sealed source (except an energy compensation source (ECS)) must be tested at intervals not to exceed 6 months. In the absence of a certificate from a transferor that a test has been made within the 6 months before the transfer, the sealed source may not be used until tested.

What is ASTM D1557?

ASTM D1557 : Standard Test Methods for Laboratory Compaction Characteristics of Soil Using Modified Effort (56,000 ft-lbf/ft3 (2,700 kN-m/m3))

What is in-place density?

In-place density is a critical property of CIR pavements for good long-term performance. There is no standard procedure for measuring the in-place density of the compacted CIR during construction. The sand cone method proved reliable for measuring the in-place density of the CIR layer during construction.

What is ASTM D698?

ASTM D698 – 12(2021) Standard Test Methods for Laboratory Compaction Characteristics of Soil Using Standard Effort (12,400 ft-lbf/ft<sup>3</sup> (600 kN-m/m<sup>3</sup>))

What's the safest level of radiation?

Adult: 5,000 Millirems. The current federal occupational limit of exposure per year for an adult (the limit for a worker using radiation) is “as low as reasonably achievable; however, not to exceed 5,000 millirems” above the 300+ millirems of natural sources of radiation and any medical radiation.

What does Alara stand for?

ALARA stands for “as low as reasonably achievable”. This principle means that even if it is a small dose, if receiving that dose has no direct benefit, you should try to avoid it. To do this, you can use three basic protective measures in radiation safety: time, distance, and shielding.

What property of nuclear radiation is most harmful?

It depends on whether your exposure to radiation is internal or external. Alpha particles are the most harmful internal hazard as compared with gamma rays and beta particles. Radioactive materials that emit alpha and beta particles are most harmful when swallowed, inhaled, absorbed, or injected.

When transporting a gauge you can safely secure block and brace it?

When transporting a gauge you can safely secure, block and brace it in the front seat. The time it takes for a radioactive material to decay to ½ its activity/strength is known as a half-death.

How do you measure soil density?

The wet weight of the recovered excavated soil is divided by the test hole volume to determine the wet density. Dry density is calculated by dividing the weight of the wet soil by its water content in percent.

What are some advantages of nuclear gauges?

Portability. One person can easily transport a typical nuclear density gauge.
Quick results. Most nuclear gauges allow both one and four minute readings. …
Virtually non-destructive. Used in the backscatter mode, the nuclear density gauge is entirely non-destructive.

Is soil a code test?

IS CodeTitleDownload LinkIS 2720-5 1985Methods of test for soils, Part 5: Determination of liquid and plastic limitDownloadIS 2720-6 1972Methods of test for soils, Part 6: Determination of shrinkage factorsDownload

How do you get to 95 compaction?

95% compaction requires the soil placed as engineered fill to have a density of at least 95% of the maximum laboratory density as determined by the method specified in the project specifications. It is 95% of the maximum density determined by the Standard Proctor Compaction Test on your soil.