|
|
Concrete Mix Design Problem 1 - Proportion A Concrete Mix For Basement Floor Slab:
|
Design an initial 3500 psi concrete mix design for concrete not subject to severe weathering or sulfate attack to be used for a basement floor slab. Use the following mix ingredients.
Slump: maximum of 4 inches.
Cement: type I non-air entrained cement with specific gravity of 3.15.
Course aggregate: maximum aggregate size of 1.5 inches, specific gravity of 2.68, dry-rodded weight of 100 pcf, absorbed moisture of 2% and moisture absorption of 0.5%.
Fine aggregate: fineness modulus of 2.8, specific gravity of 2.64, absorbed moisture of 6% and moisture absorption of 0.7%.
|
1. From the concrete mix design submenu open the concrete mix design calculation, ConcreteMix.aspx. Input the "Title" of the calculation, the "Designer/Checker" information and the known variables. Note, you do not need to enter the specific gravities for the weight basis calculation.
Next open the design reference and determine the % entrained air, water cement ratio, the course aggregate volume, the weight of water and the estimated mix design weight from the appropriate tables. The water cement ratio for 3500 psi is interpolated from the table to be approximately 0.62. Check the button to calculate by "Weight Basis" and click on the "Calculate" button. Read the results.
|
|
2.
Now check the button to calculate by "Volume Basis". Input the specific gravities of the course and fine aggregate, and click on the "Calculate" button. Read the results.
|
|
3. Summary
|
The Weight Basis mix design is as follows.
Water: 198.68 lb/cy
Cement: 483.87 lb/cy
Course Aggregate: 1955.34 lb/cy
Fine Aggregate: 1451.28 lb/cy
The Volume Basis mix design is as follows.
Water: 201.42 lb/cy
Cement: 483.87 lb/cy
Course Aggregate: 1955.34 lb/cy
Fine Aggregate: 1396.52 lb/cy
|
|
|