Concrete Testing Flashcards
1
Q
Measuring compressive strength
A
- After 7 days and 28 days test using compressive machine
- Cubes crack from corners as they are weakest
2
Q
Measuring tensile strength
A
- Perform INDIRECT tensile testing
- Apply indirect compressive load to concrete (expands both sides)
- Either do a splitting test or flexural test
3
Q
Splitting test
A
- Brazilian test
- Apply pressure on top and bottom and sample will expand sideways
4
Q
Flexural test
A
- Load from top centrally and bottom sides
- Looking for cracks that appear
5
Q
Vebe Test
A
- Flat face pushing down and vibrating on mould to fill it up
- Works well with low workability concrete
- Range of 4-25 for results typically
6
Q
3 workability tests
A
- Slump test
- Slump flow test
- Vebe test
7
Q
Slump flow test
A
- Poured into cone in one go without compaction
- Cone is removed and measure time taken to reach 500mm diameter and final diameter at end of test
8
Q
Strength Tests
A
- Compressive
- Tensile (splitting and flexural)
9
Q
Flexural Test
A
- Focus on the bend
- Press down in the middle and up at both ends
- Fb = (PL/bd2)
- b = beam width mm
- d = beam depth mm
- L = distance between supports mm
10
Q
Slump Test
A
- Poured into cone and compacted at equal levels with a pole
- Cone is removed and measure distance between full heigh and slumped height
- Visually seeing segregation gives you extra info you cannot get from other tests
