Kelly Ball Test | Workabiltiy of concrete by Kelly Ball test

Kelly Ball Test:-

Workability of concrete is very important property of concrete. 

For determination of the workability of concrete, it requires a huge amount of data & involves lengthy calculations. 

Many researchers have used various methods to measure the workability of the concrete.

After few years, they successfully found some  tests, which are the most important to check the workability. 

The test has been invented & determined by Kelly.

Due to these reason, this test was known as Kelly Ball Test or concrete ball test.

Kelly ball test is a simple field test which are very helpful for determination of the workability of concrete.

Kelly ball test has been proved that, it can be performed faster & provides accurate results with great precision than the slump test.

The one main disadvantage of these Kelly ball test, that it requires a large amount of concrete.

If we compare it with the slump test of concrete.

The Kelly ball test was earlier standardized as ASTM C360-92: “Standard Test Method for Ball Penetration in Freshly Mixed Hydraulic Cement Concrete.” 

In 1999, due to lack of use, the ASTM standard was suspended 

The Kelly ball test has never been used widely outside the U.S (Bartos 1992). 

Indian Standards does not covered this Kelly ball test.

.

Apparatus of Kelly ball test :

For this test, we require the following apparatus which consists of a cylinder with one end having a hemispherical shape of 15 cm weighing 13.6 kg,

The other end is attached to a graduated scale as well as the handle. 

The whole arrangement is secured on a fixed stand.

The results have been specified by measuring the penetration made by the hemisphere.

If it is freely placed on fresh concrete. 

We can measure the impression by a graduated scale immediately.

Procedure for Kelly ball test:

1. For performing the test, firstly we have to Freshly mixed concrete to be poured into a container up to a depth of 20cm. 
2. Once the container is filled with the concrete, the top surface is leveled & struck off the excess concrete.
3. The Kelly ball setup have to be kept on concrete. 
4. By holding the handle of hemisphere such that the frame touches the surface of the concrete.
5. We have to ensure that the setup is kept at minimum 23 cm away from the container ends. We have to just, Place at the middle portion of the container 
6. After that, we have to release the handle as well as allow the ball to penetrate through the concrete. 
7. Once the ball has been released, the depth of penetration is immediately shown in the graduate scale to the nearest 6 mm.
8. We have to, Note down the depth of penetration from the attached graduated scale.
9. Repeat the same procedures or steps for three times at different portions in the container, after that we have to do average the value.

Formula for Kelly ball test:-

The results of the Kelly ball test is correlated with the Slump test.

Advantages of Kelly ball test:

1. The Kelly ball test results are more accurate as compared with the slump test.
2. This test is a simple to perform as well as easily can be perform on site.
3. This test doesn’t any require lengthy calculation, to find the workability of concrete.

Disadvantages of Kelly ball test:

1. Kelly ball test is not suitable to use for larger size aggregates.
2. The surface of the concrete should be leveled to test the concrete.
3. This test is not recognized and used by Indian standards.
4. Due to large size aggregate, the results may vary. 

For reference, take reference of below video for easy understanding :

Video 1 :

Video 2 :

Thankyou friends for reading my Blog.  I hope you definitely like these bolg. 

For such new Blog releated updates, subscribe to our website. Thankyou.