Tag Archives: tests for workability of concrete

Vee Bee Consistometer test – Workability of concrete

Vee Bee Consistometer Test is a reliable laboratory method used to evaluate the workability of concrete, especially for stiff and low-workability mixes where slump test results are not accurate. The Vee Bee Consistometer test for workability of concrete measures the time required for concrete to remould under vibration, providing a clear indication of consistency. In the workability of concrete Vee Bee test, vibration energy replaces gravity-based flow, making it suitable for dry mixes. Understanding the Vee Bee test procedure helps engineers achieve consistent and repeatable results. The Vee Bee Consistency test of concrete is widely used in laboratories and quality control setups and is considered one of the most dependable tests for workability of concrete for controlled assessment of stiff concrete mixes.

This article explains the Vee Bee Consistometer test, its principle, procedure, applications, and importance in accurately assessing the workability of stiff concrete mixes.

Significance of Quality tests on concrete

Quality tests on concrete are essential for ensuring strength, durability, and performance in construction. These tests help engineers assess the workability of fresh concrete and the quality of hardened concrete. Common quality tests on concrete include checks during the production stage (on fresh concrete before placing), tests on hardened concrete specimens, and evaluations performed directly on finished structures. Including tests like the flow table test for concrete ensures reliable results and consistent quality throughout a project.

A construction worker in a safety vest and hard hat examines concrete samples next to a compression testing machine in a lab setting.
A civil engineer in a safety helmet and reflective vest analyzing concrete test specimens in a lab, showcasing the importance of quality control in concrete workability tests.

Quality tests performed on concrete are classified into

  • Production stage quality tests ( On fresh concrete before placing)
  • Hardened stage quality tests ( hardened concrete specimens)
  • Non Destructive tests On structures ( tests done on the structures )

Also read : Aggregate Crushing test – Strength of aggregate

Also read : 9 lab tests of Bitumen for flexible pavements

Production stage quality tests on fresh concrete

Production stage quality tests on fresh concrete are crucial for ensuring the right workability and consistency before placement. These tests help engineers select the best mix for construction and maintain quality control. Key tests include the slump test, compaction factor test, Vee-Bee test, Kelly ball test, and the flow table test for concrete.

This article focuses on the Vee Bee Consistometer test, explaining its procedure, importance, and how it compares with other workability tests like the slump test and compaction factor test.

Vee Bee Consistometer test for workability of concrete

The Vee Bee Consistometer Test is a laboratory test used to determine the workability of concrete, particularly stiff and low-workability mixes. It measures the time required for fresh concrete to remould from a conical shape into a cylindrical shape under controlled vibration. This time, known as the Vee Bee time, indicates concrete consistency. Unlike the slump test, the Vee Bee Consistometer test for workability of concrete is suitable for dry mixes that do not flow easily. Commonly used in quality control, this test helps engineers compare mix designs and ensure uniform concrete performance.

A steel laboratory apparatus used for material testing, featuring a cone-shaped container and a mechanical device for precise measurements.
Vee Bee Consistometer apparatus used for evaluating the workability of concrete in laboratory settings.

Relevant Codes and Standards for Vee Bee Consistometer Test

  • IS 1199 (Part 2): 2018Methods of Sampling and Analysis of Concrete – Workability
    Issued by Bureau of Indian Standards.
    This standard covers the Vee Bee Consistometer test, along with slump and compaction factor tests.
  • BS EN 12350-3Testing Fresh Concrete – Vebe Test
    Issued by British Standards Institution.
    Widely used in the UK and Europe for stiff concrete workability assessment.
  • DIN 1048 (Part 1)Testing Concrete – Fresh Concrete Tests
    Issued by DIN.
    Includes the Vebe test for consistency measurement.

Note: These standards ensure uniform testing procedures, repeatable results, and reliable evaluation of low-workability concrete mixes.Relevant IS code

Apparatus used for Vee Bee Consistometer

A blue industrial machine with a funnel and a black container at the center, designed for processing materials.
Vee Bee Consistometer apparatus used to assess the workability of concrete.

The Vee – Bee Consistometer includes of 

  • A vibrator table resting upon elastic supports
  • A metal pot
  • A sheet metal cone, open at both ends
  • A standard iron rod

The dimension of the vibrating table is 380 mm in length, 260 mm in width and height of 305 mm. Also, supporting the table there is a rubber shock absorber. Under the table, there is a vibrator that vibrates electrically.  The dimension of the metal slump cone is 300mm height, 200 mm top diameter and 100 mm bottom diameter. 

A person pouring a scoop of material into a metallic measuring cone on a balance scale, with a blue background.
The Vee Bee Consistometer, essential for evaluating the workability of concrete, particularly in stiff and low-workability mixes.

Test procedure

  • Initially fill the slump cone with four layers of concrete. Each layer should have a height of one – fourth of the cone. 
  • After that tamp each layer 25 times using a standard tamping rod and strike uniformly.
  • Then after placing the final layer, remove the excess concrete on the top of the concrete.
  • Move and place the swivel arm attached to the glass disc on the top of the cone.
  • Now remove the cylindrical cone gradually in the vertical direction and note down the slump.
  • Then switch on the electrical vibrator and allow the concrete to spread. 
  • The time taken by the concrete to spread uniformly is noted using the stop clock.
  • This time is expressed in vee bee seconds.

The time for the concrete to remould is the Vee-Bee seconds. The Vee Bee consistometer is an indirect measure of concrete workability. This method is suitable for concrete whose slump value cannot be determined. ie, for dry mixes. We can get direct result through this method.

Also Read : Soundness test on aggregate

Key Takeaways

  1. The Vee Bee Consistometer Test is designed to assess the workability of stiff concrete mixes.
  2. It measures the time required for concrete to remould under vibration.
  3. Longer Vee Bee time indicates lower workability of concrete.
  4. The test provides more reliable results than slump test for dry mixes.
  5. It is commonly used in laboratory-controlled environments.
  6. The method helps compare different concrete mix designs.
  7. Proper vibration is essential for accurate results.
  8. The test minimizes subjective judgment during workability assessment.
  9. It is standardized under Indian and international codes.
  10. The test is an important part of quality control procedures.
  11. It complements other tests for workability of concrete.
  12. It ensures consistency during concrete production.

Conclusion

The Vee Bee Consistometer Test plays a crucial role in evaluating the workability of concrete, especially for mixes with low water content. By measuring the remoulding time under vibration, the test provides a clear and quantitative indication of concrete consistency. Unlike the slump test, it performs well for stiff mixes where flow is minimal. When conducted according to standard procedures, the test helps engineers maintain uniformity in concrete production and placement. It also supports effective quality control by enabling comparison of different mix proportions. As one of the reliable laboratory-based tests for workability of concrete, the Vee Bee Consistometer Test remains essential for achieving durable and well-performing concrete structures.

Kelly Ball Test – Workability of Concrete

Kelly Ball Test is a simple and reliable method used to assess the workability of concrete directly at construction sites. Among the various tests for workability of concrete, this method stands out for its speed. It is also easy to execute on fresh concrete surfaces. The Kelly Ball Test concrete assessment works by measuring penetration depth. This makes it a practical Kelly Ball penetration test for large pours and ready-mix applications. To ensure accurate results, you must follow the standard Kelly Ball Test procedure. This procedure correlates penetration values with concrete consistency. The Kelly Ball Test is simple. It is also suitable for the field. Therefore, it continues to be an effective tool for monitoring concrete quality during placement.

  1. Significance of Quality tests on concrete
  2. Production stage quality tests on fresh concrete
  3. What is Kelly ball test ?
    1. Standard Guidelines
      1. Codes and Standards
    2. Kelly ball test Apparatus as per ASTM C360/C360 M 92
    3. Test Procedure
    4. Results
  4. Advantages – Kelly ball test
  5. Disadvantages of Kelly Ball Test
  6. Key Takeaways
  7. Conclusion

Significance of Quality tests on concrete

Quality tests on concrete are essential for ensuring strength, durability, and performance in construction. These tests help engineers assess the workability of fresh concrete and the quality of hardened concrete. Common quality tests on concrete include checks during the production stage (on fresh concrete before placing), tests on hardened concrete specimens, and evaluations performed directly on finished structures. Including tests like the flow table test for concrete ensures reliable results and consistent quality throughout a project.

Quality tests performed on concrete are classified into

Also read : Bitumen tests – 9 lab tests for bitumen

Production stage quality tests on fresh concrete

This article covers the kelly ball test ,apparatus details, procedure, merits and demerits etc.

A Kelly ball test apparatus placed on a construction site, with blurred machinery and materials in the background.
The Kelly Ball Test apparatus used for assessing the workability of concrete at construction sites.

What is Kelly ball test ?

This simple field method assesses the workability of freshly mixed concrete. In the test, a standard steel ball penetrates the concrete under its own weight, and the penetration depth indicates concrete consistency. Engineers mainly use this test at construction sites to make quick decisions during concrete placement. The Kelly Ball Test helps verify whether the concrete is too stiff or too workable for proper compaction and finishing. Its significance lies in its speed, ease of use, and ability to provide a direct indication of concrete workability without complex equipment.

Standard Guidelines

Standard codes for the Kelly Ball penetration test provide guidance on equipment, testing procedure, and result interpretation. This ensures reliable assessment of concrete workability, especially during on-site quality control.

Codes and Standards

ASTM C360 / C360M 92– Standard Test Method for Ball Penetration in Freshly Mixed Concrete
Issued by ASTM International.
Note: This standard has been withdrawn but is still referenced in technical literature.

AASHTO T 183 – Ball Penetration Test
Issued by AASHTO.
Note: This standard is discontinued and mainly used for historical reference.

Indian Standards (IS Codes)
There is no specific IS code . Workability testing in India is generally covered under IS 1199, issued by Bureau of Indian Standards

Kelly ball test Apparatus as per ASTM C360/C360 M 92

The kelly ball apparatus for measuring the workability of concrete consist of..

  • Meta hemisphere (Ball)
  • Graduated scale
  • Frame
  • Handle

The workability of concrete is decided by the depth of the penetration of metal hemisphere (ball) which will descend under its own weight into the fresh concrete. The Metal hemisphere or ball has 152 mm diameter and 13.6 kg weight. J. W. Kelly (Professor, University of California) had devised the plan of the Kelly ball test afessor, University of California) had devised the plan of the Kelly ball test apparatus. Hence, later on it also came to be known as a ball penetration test. On the top of the apparatus, there is a handle. The graduated scale measures the penetration reading. 

A three-part image illustrating the Kelly Ball Test procedure. The left panel shows the apparatus used for the test, the middle panel features a diagram explaining the components, and the right panel displays a person conducting the on-site test with concrete.
Visual representation of the Kelly Ball Test procedure, showcasing the apparatus, diagram, and on-site testing process for assessing concrete workability.

Test Procedure

  • Place freshly mixed concrete on a level, rigid surface immediately after mixing.
  • Ensure the concrete surface is smooth and free from vibration.
  • Clean the Kelly ball and check that it moves freely along the guide rod.
  • Position the apparatus so the steel ball just touches the concrete surface.
  • Release the ball gently without applying any force.
  • Allow the ball to penetrate under its own weight.
  • Wait until the penetration stabilizes.
  • Read and record the depth of penetration from the graduated scale.
  • Repeat the test at different locations on the concrete surface.
  • Take the average penetration value as the final result.
  • Note: Greater penetration indicates higher workability, while lower penetration indicates stiffer concrete.

Results

The workability of the concrete is the average value of the readings from the penetration.

Advantages – Kelly ball test

Some advantages of this test are

  • Compared to other workability tests kelly ball test is very fast
  • Precise and Accurate results

Disadvantages of Kelly Ball Test

The disadvantages of this test include

  • This test requires a large amount of fresh concrete.
  • The result should not be precise if the size of the aggregate is large.
  • The concrete should be levelled before starting the test.

Key Takeaways

  • This is a simple field method for assessing fresh concrete consistency.
  • It directly measures penetration depth, reflecting the workability of concrete.
  • The test is faster and less operator-dependent than many laboratory methods.
  • Kelly Ball Test concrete assessment is suitable for large pours and flat surfaces.
  • The Kelly Ball penetration test works under the self-weight of the steel ball.
  • Proper surface preparation is essential for reliable results.
  • The procedure must be followed carefully to avoid errors.
  • It is mainly used as a supplementary field check.
  • Results help engineers make quick placement decisions.
  • It complements other tests for workability of concrete used in quality control.

Conclusion

The Kelly Ball Test remains a practical and efficient method for evaluating the workability of concrete under site conditions. By measuring penetration depth, the Kelly Ball penetration test provides a direct indication of concrete consistency during placement. Although not as widely standardized as slump testing, Kelly Ball Test concrete assessment is valuable for large slabs and mass concreting works. When carried out correctly using the recommended Kelly Ball Test procedure, it helps engineers maintain uniform quality and avoid placement issues. Among various tests for workability of concrete, the Kelly Ball Test stands out for its simplicity, speed, and field applicability. Used alongside standard methods, it supports better decision-making and effective on-site concrete quality control.