Determining the Workability of Fresh Concrete by Slump Test

Table of Contents Title: 1

Aim: 1

Apparatus: 1

Procedure 2

Theory: 2

Results: 4

Discussion: 5

Conclusion: 5

Title: Slump of Fresh Concrete

Aim: To measure the slump or workability of fresh concrete

Apparatus:

• 1 Electronic scale (capacity 8100g accurate to 0.1g, inherent error ± 0.05g)

• Shovel

• Stainless steel tamping rod(diameter =5/8˝, length =18˝)

• Mould

• Metal scoops

• Ruler

• Slump cone

• Plastic bucket

• Fine aggregate(4.75 mm)

• Coarse aggregate (25mm)

• Tap water

• Ordinary Portland cement(manufactured 7/02/2011)

• 100ml of Admixture (Air Entrain)

Procedure

1. The cone was dampened and placed on a flat surface.

2. The cone was then filled in three layers with the operator standing on the foot pieces, rodding 25 times for each layer.

3. The top of the concrete in the cone was leveled off to the cone

4. The cone was lifted vertically, without any sideway or vibration motions, until it was clear of the concrete.

5. The cone was then set beside the concrete sample; the rod was placed perpendicularly to the top of the cone and the decrease in height of the concrete sample measured.

Theory:

Fresh concrete is a homogenous mixture of water, cement, aggregates (coarse and fine), air and in some cases admixtures may be used. Admixture is used in certain cases to control rheology, rate of setting, hardening and durability. After mixing the constituent materials to produce a uniform blend, operations such as transporting, compacting, placing and the finishing of fresh concrete can all affect the properties of hardened concrete. It is important that the constituent materials remain s uniformly distributed within the concrete mass during the various stages of its handling and also that full compaction is achieved. Whenever these conditions are not