Utilization of Water-Cooled and Air-Cooled Slag Aggregate in Concrete: A Solution to the Secular Economy
Abstract
:1. Introduction
2. Materials and Methods
2.1. Material
2.2. Mix Design, Preparation of Samples, and Curing
2.3. Testing
3. Results and Discussion
3.1. Consistency
3.2. Compressive Strength
3.3. Tensile Strength
4. Conclusions
- Increasing the replacement of fine aggregate by water-cooled slag (0–100%) significantly decreases the workability of concrete. Increasing the replacement of coarse aggregate by air-cooled slag (0–100%) increases the workability of concrete.
- Replacement of fine aggregate with water-cooled slag up to 50% has no influence on the compressive strength, as the same compressive strength for both mixes is obtained. Meanwhile, increasing the replacement up to 100% leads to a significant decrease in compressive strength by 56% than that of the control mix.
- Replacement of coarse aggregate with slag aggregate up to 50% increases the compressive strength by 6%, while increasing the replacement over 50% slightly decreases the compressive strength. This means that the replacement of coarse aggregate alone has trivial influence on compressive strength.
- The replacement of natural aggregate has an insignificant effect on the tensile strength of mixes.
Author Contributions
Funding
Conflicts of Interest
References
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Constituents | SiO2 | Al2O3 | CaO | Fe2O3 | MgO | Na2O | K2O | SO3 | TiO2 | P2O5 | MnO | Cl | Ignition Loss |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Cement | 20.13 | 5.32 | 61.63 | 3.61 | 2.39 | 0.37 | 0.13 | 2.87 | - | - | - | - | ≤0.01 |
Slag | 38.25 | 7.64 | 34.2 | 0.53 | 7.73 | 1.14 | 1.35 | 3.01 | 0.54 | ≥0.01 | 5.17 | 0.18 |
Property | Sand | Gravel | ACS | WCS |
---|---|---|---|---|
Specific Weight | 2.89 | 2.76 | 3.54 | 2.5 |
Bulk Density | 1.67 | 1.82 | 1.9 | 1.52 |
Fineness Modulus | 2.75 | - | - | - |
Water Absorption (%) | - | 1.85 | 0.922 | 2 |
Crushing Value (%) | - | 14.3 | - | - |
Clay and Fine Dust Content (%) | 1.95 | 0.55 | - | - |
MIX ID | Cement | Fine Agg. (Sand) | Coarse Agg. (Dolomite) | WCS | ACS | Water | S.P (1.6%) |
---|---|---|---|---|---|---|---|
Control (C) | 390 | 714 | 1071 | 0 | 0 | 175.5 | 6.24 |
F50 | 390 | 357 | 1071 | 357 | 0 | 175.5 | 6.24 |
F75 | 390 | 178.5 | 1071 | 535.5 | 0 | 175.5 | 6.24 |
F100 | 390 | 0 | 1071 | 714 | 0 | 175.5 | 6.24 |
C50 | 390 | 714 | 535.5 | 0 | 535.5 | 175.5 | 6.24 |
C75 | 390 | 714 | 267.75 | 0 | 803.25 | 175.5 | 6.24 |
C100 | 390 | 714 | 0 | 0 | 1071 | 175.5 | 6.24 |
F50 + C50 | 390 | 357 | 535.5 | 357 | 535.5 | 175.5 | 6.24 |
F50 + C75 | 390 | 357 | 267.75 | 357 | 803.25 | 175.5 | 6.24 |
F50 + C100 | 390 | 357 | 0 | 357 | 1071 | 175.5 | 6.24 |
F75 + C50 | 390 | 178.5 | 535.5 | 535.5 | 535.5 | 175.5 | 6.24 |
F75 + C75 | 390 | 178.5 | 267.75 | 535.5 | 803.25 | 175.5 | 6.24 |
F75 + C100 | 390 | 178.5 | 0 | 535.5 | 1071 | 175.5 | 6.24 |
F100 + C50 | 390 | 0 | 535.5 | 714 | 535.5 | 175.5 | 6.24 |
F100 + C75 | 390 | 0 | 267.75 | 714 | 803.25 | 175.5 | 6.24 |
F100 + C100 | 390 | 0 | 0 | 714 | 1071 | 175.5 | 6.24 |
MIX ID | 28-Days Compressive Strength (Mpa) | Mean | S.D. | C.V. | ||
---|---|---|---|---|---|---|
Control (C) | 38.6 | 39.7 | 38.3 | 38.9 | 0.7 | 0.019 |
F50 | 35.4 | 41.4 | 38.2 | 38.3 | 3.0 | 0.078 |
F75 | 37 | 41.1 | 38.8 | 39.0 | 2.1 | 0.053 |
F100 | 17.7 | 17 | 15.9 | 16.9 | 0.9 | 0.054 |
C50 | 43.5 | 39.1 | 42 | 41.5 | 2.2 | 0.054 |
C75 | 36.9 | 36.3 | 36.3 | 36.5 | 0.3 | 0.009 |
C100 | 38.6 | 37 | 40.2 | 38.6 | 1.6 | 0.041 |
F50 + C50 | 34.4 | 32.1 | 34 | 33.5 | 1.2 | 0.037 |
F50 + C75 | 33.4 | 32.3 | 33.3 | 33.0 | 0.6 | 0.018 |
F50 + C100 | 22.6 | 27.8 | 20.7 | 23.7 | 3.7 | 0.155 |
F75 + C50 | 20.8 | 18.1 | 21.5 | 20.1 | 1.8 | 0.089 |
F75 + C75 | 25 | 30.6 | 27.4 | 27.7 | 2.8 | 0.102 |
F75 + C100 | 39.2 | 37.8 | 35 | 37.3 | 2.1 | 0.057 |
F100 + C50 | 24.2 | 25.1 | 27 | 25.4 | 1.4 | 0.056 |
F100 + C75 | 24 | 24.9 | 26 | 25.0 | 1.0 | 0.040 |
F100 + C100 | 31.7 | 30.5 | 32.5 | 31.6 | 1.0 | 0.032 |
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El-Tair, A.M.; Bakheet, R.; El-Feky, M.S.; Kohail, M.; Akib, S. Utilization of Water-Cooled and Air-Cooled Slag Aggregate in Concrete: A Solution to the Secular Economy. Eng 2020, 1, 48-59. https://doi.org/10.3390/eng1010004
El-Tair AM, Bakheet R, El-Feky MS, Kohail M, Akib S. Utilization of Water-Cooled and Air-Cooled Slag Aggregate in Concrete: A Solution to the Secular Economy. Eng. 2020; 1(1):48-59. https://doi.org/10.3390/eng1010004
Chicago/Turabian StyleEl-Tair, Ahmed Maher, Ramez Bakheet, Mohamed Samy El-Feky, Mohamed Kohail, and Shatirah Akib. 2020. "Utilization of Water-Cooled and Air-Cooled Slag Aggregate in Concrete: A Solution to the Secular Economy" Eng 1, no. 1: 48-59. https://doi.org/10.3390/eng1010004
APA StyleEl-Tair, A. M., Bakheet, R., El-Feky, M. S., Kohail, M., & Akib, S. (2020). Utilization of Water-Cooled and Air-Cooled Slag Aggregate in Concrete: A Solution to the Secular Economy. Eng, 1(1), 48-59. https://doi.org/10.3390/eng1010004