Table of Contents
Does slump affect the strength of concrete?
“Wetness” of concrete as measured by the slump test is directly related to its compressive strength – the 28 day compressive strength of concrete is reduced by about 1.5 MPa for each additional 20mm of slump produced by adding water.
How does slump affect concrete?
Concrete with a low slump has a high proportion of cement to water that makes it difficult to work with but provides it with greater strength. Each inch of slump that you add to your concrete mixture will decrease the effort required to work it.
What happens if concrete slump is too high?
As you increase the amount of water in a mix, you also increase the porosity of the hardened concrete. Excessive slump also can result from accidentally adding too much water-reducing admixtures or super-plasticizers to a mix. This can result in aggregate segregation and a serious loss of strength.
Why is slump important in concrete?
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 is the minimum slump for 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 a good slump for concrete?
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. Admixtures should be used instead of water to achieve higher slumps so that you can maintain the quality of your concrete.
How do you fix high slump in concrete?
First, the high slump could be due to incorrect amount of plasticizers being added. Second, just adding cement will not give you the same mix design. You also need to add the fine aggregate and coarse aggregate proportionally also in order to achieve the original mix design.
What is the normal slump of concrete?