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The Slump Set

By July 14, 2021July 20th, 2021No Comments

You will need the following equipment –

1. Buckets or wheelbarrow

2. Cloth

3. Mixing tray

4. Sampling scoop

5. Sampling and testing certs

6. Slump cone and rigid metal plate

7. Slump tamping rod

8. Small scoop

9. Square mouthed shovel

10. Steel rule

Step 1

· Empty the sampling buckets on to the mixing tray

· Scrape each bucket clean

Step 2

· Thoroughly remix the sample shovelling into a heap

· Turn the heap over to form another

· Do this three times

Step 3

· Flatten the final heap by repeatedly digging in the shovel vertically

· Lift the shovel clear each time

· If the alternative method of sampling has been used, divide this heap into two and test each part

Step 4

· Ensure the slump cone is clean and damp

· Place the metal plate on a solid level base

· Place a cone on the plate and stand on the foot pieces

Step 5

· Fill the cone in three equal depth layers

· Use the standard slump tamping rod

· Rod each layer 25 times

· Spread the blows evenly over the area

· Make sure the rod just penetrates the layer below

· Heap the concrete above the top of the cone before rodding the       third layer

Step 6

· Top up if necessary

· Use the rod with a sawing and rolling motion to strike the concrete

  level with the top of the cone

Step 7

· Carefully clean off spillage from side and base plate   

Step 8

· Carefully lift the cone straight up and clear to a count of

  between 5 and 10 seconds

Step 9

· Lay the rod across the upturned slump cone

· Measure the distance between the underside of the rod and             highest point of the concrete – the true slump

· Record this distance to the nearest 5mm

· In all cases record the kind of slump

· Check the type of slump

· If the slump isn`t true, take a new sample and repeat the test

· Complete the sampling and testing certificates

Types of Slump  There are three kinds of Slump

True

Shear

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True

Shear

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