BeginnerTopic 11 of 112Civil & Structural
Workability and slump test
Slump measures the consistency of fresh concrete.
In depth
Workability is the ease of mixing, placing and compacting without segregation. The slump test lowers a cone's fresh concrete height: 25–50 mm low, 50–100 mm medium, >100 mm high workability. Alternatives: compaction factor, flow table and V-funnel for self-compacting concrete.
Key points
- Slump depends on water content
- Bleeding and segregation
- Time loss in hot weather
ExampleA typical pumped concrete has 100–150 mm slump.
What is Workability and slump test?
Slump measures the consistency of fresh concrete.
Why is it important to understand workability and slump test?
Workability decides whether fresh concrete can be placed and compacted properly, and the slump test is the quick field check.
What does a slump test measure?
The drop of a cone of fresh concrete after it is lifted, which indicates its consistency and workability.
What slump is typical for a slab?
Many slabs use medium slumps around 75 to 100 mm, but the right value depends on the placing method and the element.
How is Workability and slump test used in practice?
Typical applications include checking the slump of a truck of concrete before pouring a slab, deciding whether a mix is stiff enough for a vibrated column and confirming a flowing mix for a congested reinforced wall.
What should I learn before Workability and slump test?
Study "Water-cement ratio" first (topic 10 of 112 in Civil & Structural). It covers the groundwork this topic builds on.
What are the key points of Workability and slump test?
Slump depends on water content. Bleeding and segregation. Time loss in hot weather.
Can you give an example of Workability and slump test?
A typical pumped concrete has 100–150 mm slump.
What comes after Workability and slump test?
The next topic is "Curing of concrete", which builds directly on this one.
How difficult is Workability and slump test?
It is classed as Beginner in Civil & Structural (topic 11 of 112). It is an entry-level topic. It relies only on basic school mathematics and the ideas introduced earlier in this discipline.