1. Assessment of a Simple Test to Evaluate Concrete Permeability
Presenter: Erica Mack
Acknowledgements: Peter Taylor, Xuhao Wang

2. 40% the concrete state 20% background
Percentage of paved roads within Iowa that are paved with concrete
the
concrete
40%
Percentage of paved roads within the United States that are paved with concrete
state
20%

3. background

4. 1-inch Crushed Limestone
methods
water cement ratio
0.35
0.40
0.45
0.60
Cement
Slag
Class C Fly Ash
twelve
Natural River Sand
1-inch Crushed Limestone
unique
mix
designs

5. methods six samples per mixture seventy-two total samples
Air Permeability Test
Drop Absorption Test
Compressive Strength Test

6. methods
twenty
microliters of
water
3 days
7 days
56 days
28 days

7. results of the mix design
The compressive strength is lower when the water-cement ratio of the mixture is higher.

8. results and analysis
A low water cement ratio is expected to yield a lower permeability.
A lower permeability will result in a higher drop absorption time.
This property was confirmed and consistent across all twelve mix designs.

9. results and analysis
Permeability is expected to be poor when concrete is at a young age, resulting in a low drop absorption time.
Supplementing slag as a binder type creates a denser paste, increasing drop absorption time.

10. results of the air permeability test
The air permeability test was conducted to have a direct measurement of the permeability of the samples.
Drop absorption time increased linearly with the measured air permeability index.

11. conclusions Traditional Test Methods Traditional Test Methods
The drop absorption test provides permeability results that are consistent with known permeability characteristics of concrete.
The drop absorption test is faster and more localized than traditional permeability test methods.
Traditional Test Methods
Drop Absorption Test
Traditional Test Methods
Drop Absorption Test

12. current uses and future goals
The drop absorption test is being used to assess roadways within Iowa that are experiencing the common pavement distress of joint deterioration.
A classification scale is being developed to provide an indication of permeability after obtaining the drop absorption time of a sample.
The drop absorption test has the potential to be of great value to the industry.

13. thank you Thank you for listening.
Special thanks to the Concrete Pavement Technology Center, the Portland Cement Concrete Pavement and Materials Research Laboratory, and Iowa State University.