Table of Contents
- 1 Why is a slump test important?
- 2 What factors are taken into consideration in specifying the slump?
- 3 What does the slump test measure concrete?
- 4 Why is concrete slump important?
- 5 What is the purpose of mixing the concrete with the correct mixture of ingredients?
- 6 How many types of mix design are there?
Why is a slump test important?
The concrete slump test measures the consistency of fresh concrete before it sets. It is performed to check the workability of freshly made concrete, and therefore the ease with which concrete flows. The slump test is used to ensure uniformity for different loads of concrete under field conditions.
What factors are taken into consideration in specifying the slump?
Which factors influence the concrete slump test:
- Material properties like chemistry, fineness, particle size distribution, moisture content and temperature of cementitious materials.
- Size, texture, combined grading, cleanliness and moisture content of the aggregates,
How is slump value measured?
In case of a shear slump, the slump value is measured as the difference in height between the height of the mould and the average value of the subsidence.
What does the slump test measure concrete?
Concrete slump testing is a quick and easy procedure that can be performed in real-time and on-site that is used to determine the workability as well as the consistency of fresh concrete. Concrete with slump values that are too low or too high can be identified and corrected prior to use.
Why is concrete slump important?
It shows the flow and overall workability of freshly mixed concrete. Simply put, the higher the slump, the wetter the mix. Four-inch (4”) slump is very common with normal weight concrete and is a good for pumping. Slumps that are above average will cause reduced strength, durability, and permeability of the concrete.
What should be the slump value of concrete?
What is the ideal value of slump? Answer 1 In case of a dry sample, slump will be in the range of 25-50 mm that is 1-2 inches. But in case of a wet concrete, the slump may vary from 150-175 mm or say 6-7 inches.
What is the purpose of mixing the concrete with the correct mixture of ingredients?
A properly designed mixture possesses the desired workability for the fresh concrete and the required durability and strength for the hardened concrete. Typically, a mix is about 10 to 15 percent cement, 60 to 75 percent aggregate and 15 to 20 percent water.
How many types of mix design are there?
Designed Mix Ratio of Concrete
| Concrete Grade | Mix Ratio | Compressive Strength |
|---|---|---|
| M7.5 | 1 : 4 : 8 | 7.5 MPa |
| M10 | 1 : 3 : 6 | 10 MPa |
| M15 | 1 : 2 : 4 | 15 MPa |
| M20 | 1 : 1.5 : 3 | 20 MPa |