FRESH CONCRETE

Question 1

Define the concept workability

Answer 1

The property of concrete that determines its capacity to be placed and consolidated properly and be finished without harmful segregation

Question 2

Define the concept consistency

Answer 2

the relative mobility of the concrete mixture

Question 3

Define the concept stability

Answer 3

ability of concrete to stick together

Question 4

Describe briefly the slumptest. (sketch)

Answer 4

pg.86

Question 5

Describe briefly the VEBE-test (sketch)

Answer 5

pg.87

Question 6

In conection with concrete there are three types of segregation. Name and describe these

Answer 6

• “Grout segregation”
• “Bleeding or water gain”
• “Coarse particle segregation”

Question 7

There are in principle two causes for segregation of concrete. Name these.

Answer 7

• Inadequate mix design

- Excessive vibration

Question 8

What is VCT? Present a general diagram showing the realationship between compressive strenght and vct for concrete of diffrent ages.

Answer 8

pg 89

Question 9

There are two parameters that strongly affect the strength of concrete. Which?

Answer 9

• Cement contentof the concrete

- Water cement ratio

Question 10

How is the compressive strength of concrete normally determinded in Sweden?

Answer 10

By casting, curing and testing test specimens