How do you do the Clegg test?
To carry out a test, the ground surface is brushed lightly with the foot to remove loose material and the guide tube is placed in position. With the digital readout switched on and held in one hand, the hammer is raised to a height of 450 mm as indicated on the hammer head and then allowed to fall freely.
What is a Clegg reading?
The Clegg Impact Soil Tester provides a means of measuring and controlling soil strength. Used to confirm uniform compaction over wide areas of ground, identifying poorly compacted areas and ineffective rolling of materials. A backlit readout unit is held in the hand during testing.
How do you Clegg a hammer?
Raise the hammer with one hand until the white indicator ring is level with the top of the guide tube. Make sure the cable is free and will not snag as the hammer falls; then drop the hammer cleanly. Observe the meter reading.
How do you use Clegg?
Stand with both feet on the base flange, or rest one foot on the flange whilst steadying the tube with the side of the leg. remove the locking pin that retains the hammer inside the tube and unclip the meter unit. Press the button on the readout and check the display shows zero IV (Impact Value).
What is a good CBR test result?
A good quality laboratory load frame with a capacity of 10,000lbf (44.5kN) or more that can operate at a strain rate of 0.05in (1.3mm) per minute is suitable for CBR penetration testing.
How do you read a CBR test?
The CBR test is performed by measuring the pressure required to penetrate a soil sample with a plunger of standard area. The measured pressure is then divided by the pressure required to achieve an equal penetration on a standard crushed rock material. The harder the surface, the higher the CBR value.
What is a good CBR value for subgrade?
in subgrade material CBR value should be nearly 15-19% .
How do I know my CBR value?
What is a good CBR value?
To understand the impact of CBR (subgrade strength) on the pavement, let’s look at some typical CBR values. A clayey soil generally has a low CBR value (less than 8). Sands are more granular and drain better and will generally have CBR values between 15 and 35. Gravel will have the best CBR values, generally 25 and up.
Does the Clegg hammer measure soil compaction?
The Clegg Hammer is similar to many other soil compaction measuring devices in that it does not provide direct readout of soil density or soil moisture values like the NDG. It monitors soil strength-stiffnessafter theapplication of impact force on the soil.
What is a Clegg hammer used for?
DESCRIPTION OF THE CLEGG HAMMER. The Clegg Hammer (also called the Clegg Impact Soil Tester) consists of a compaction hammer operating within a vertical guide tube. When the hammer strikes the soil surface, a precision accelerometer mounted on the hammer feeds its output to a digital readout unit.
What is a Clegg impact soil tester?
High quality genuine Clegg Impact Soil Tester manufactured under license to Dr. Clegg Pty Ltd (the original inventors). This apparatus is used to obtain an indication of the degree of compaction of soil. Recorded valves can be directly correlated to the CBR test method.
What is Clegg hardness test?
Initially developed for engineering purposes, named after Dr Baden Clegg. Designed to measure the hardness or shock absorption properties of a surface. Records deceleration of a mass dropped from a standard height Readings in CIV units, 1 CIV unit = 10 gravities. Widely used in Australia and New Zealand.