When the construction is going on the slump test is a very first test done on concrete on every construction site to determine the quality of concrete. The concrete slump test is a simple and widely used test to measure the consistency and workability of fresh concrete.
Slump Test for Concrete: Details, Types And Step by Step Guide.
In this blog, Let’s take a look at the concrete slump test in more detail.
Also read,
How to Choose Best Wash Basin for Your House?
Waterproofing in Building Construction: Waterproofing of Terrace.
5 Tips to Master Total Station : Survey Equipment.
The domain I use : Hostinger.
Measurement tape I use : Stanley.
The Safety shoes I use : Allen Cooper.
What is the concrete slump test?
The slump test of concrete is a field test done in reference with IS code 1199 : Part 2 : 2018. It has a guide methods of sampling, testing and analysis for determination of consistency of fresh concrete ( First Revision ). The workability of concrete can be measured with this test shows, i.e. the ease with which concrete can be mixed, transported, placed, and compacted.
The main reason to perform this test on the field is to ensure the consistency of every batch, strength and quality. The concrete slump test gives an idea about water cement ratio as a technical person you should know that high water quantity may decrease the strength of the concrete.
It is unsuitable for testing slumps less than 10 mm or greater than 210 mm, or where the aggregate size is greater than 40 mm.
Necessity Equipments and Cone Dimensions :
The cone which is used for the test has standard dimensions of size having 100 mm top diameter and 200 mm of base diameter with a height of 300 mm. For getting a good result the cone should have 1.6 mm thickness. The tapping rode used for stroke should have 600 mm length of 16 mm dia.
Before you carry out the concrete slump test, you should have important Equipment Checklist :
The Slump cone test apparatus you can buy through my link Slump Cone.
- Personal Protective Equipment,
- Small scoop,
- Compacting rod,
- Square-mouthed shovel,
- Mixing tray,
- Buckets and Steel rod,
- Slump cone and rigid metal base.
How do you carry out a slump test?
The following steps are performed to measure the concrete slump test according to the IS code:
1. Empty the sampling buckets onto the mixing tray. Scrape each bucket clean.
2. Thoroughly remix the sample, shovelling into a heap, turn the heap over to form another three times.
4. Ensure the slump cone and base plate are clean and damp but free from superfluous moisture. Place the metal plate on solid level base away from vibration or other disturbance.
5. Place the cone on the plate and stand on the foot-pieces. The next steps should not take more than 180 seconds.
6. Fill the cone in three equal depth layers of 100 mm. Use the standard compacting rod to tamp each layer 25 times. Spread the blows evenly, ensuring that the strokes are uniformly distributed over the cross-section and just penetrating into the layer below It.
7. Top up if necessary before completing the rodding of the top layer. Use the rod with a sawing and rolling motion to strike the concrete level with the top of the cone.
8. Carefully clean off spillage from sides and baseplate whilst maintaining foot pressure.
9. Carefully lift the cone straight up and clear to a count of between 2 and 5 seconds and complete the whole operation within 150 seconds.
10. Lay the rod across the upturned slump cone. Measure the distance between the underside of the rod and the highest point of the concrete.
The slump test should only be used for slump ≥ 10 mm and ≤ 210 mm. For higher workability concrete it is preferable to specify by slump-flow class.
Types of Slump :
Based on the result of concrete slump test, it will fall in mainly three categories:
True Slump retains the shape of cone purely without disintegration of concrete demonstrating the concrete has a good workability and cohesion with optimum water content.
Shear Slump shows the disintegration of half portions of upper cone shape and is not good to use as it impacts the quality of concrete.
Collapse Slump is completely fall over the base plate showing the high water content and is not good for the construction projects.
Limitations of The Concrete Slump Test :
- Slump test is only carried out on the concrete having 10 mm to 40 mm aggregate size.
- If the quantity of fine aggregates are more in the proportion then it should not be carried out.
- This test is not performed on foam concrete.
Also read more about civil engineering stuff here :
Hey there, I appreciate you posting great content covering that topic with full attention to details and providing updated data. I believe it is my turn to give back, check out my website UY4 for additional resources about Airport Transfer.