Isothermal Drying Process and its Effect on Compressive Strength of Concrete in Multiscale
Abstract
:1. Introduction
2. Materials and Methods
2.1. Materials and Sample Preparation
2.2. Test Procedures
2.2.1. Isothermal Drying Process
2.2.2. Deformation in drying process
2.2.3. Compression test
2.3. Microstructural Analyzing Techniques
3. Results
3.1. Isothermal Drying Process
3.2. Compression Test
3.2.1. Compression Strength
3.2.2. Failure Mode
3.3. Drying Deformation
3.4. Microstructure Analysis
3.4.1. TGA/DSC Analysis
3.4.2. MIP Results Analysis
3.4.3. SEM Analysis
4. Discussion
5. Conclusions
Author Contributions
Funding
Conflicts of Interest
References and Note
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Density/kg·m−3 | Initial Setting Time/min | Final Setting Time/min | Soundness | Compressive Strength at 28 Days/MPa |
---|---|---|---|---|
3150 | 90 | 320 | qualified | 37.3 |
Fineness Modulus | Dense Packing Density/kg·m−3 | Apparent Density/kg·m−3 | Clay Content/% |
---|---|---|---|
2.54 | 1764 | 2560 | 0.7 |
Particle Size/cm | Bulk Density/kg·m−3 | Apparent Density/kg·m−3 | Clay Content/% |
---|---|---|---|
5–20 | 1638 | 2680 | 0.5% |
Material | Water/Cement Ratio | Cement/kg | Water/kg | Fine Aggregate/kg | Coarse Aggregate/kg |
---|---|---|---|---|---|
cement paste | 0.35 | 1498 | 524 | - | - |
0.38 | 1434 | 545 | - | - | |
0.41 | 1375 | 564 | - | - | |
mortar | 0.35 | 690 | 242 | 1381 | - |
0.38 | 676 | 257 | 1352 | - | |
0.41 | 663 | 272 | 1326 | - | |
concrete | 0.35 | 368 | 129 | 735 | 1252 |
0.38 | 364 | 138 | 727 | 1239 | |
0.41 | 360 | 148 | 720 | 1225 |
Water/Cement Ratio | Material | Mass Fraction of Paste/% | Time Required to Completely Dry State/h | Water Loss (by Mass)/% | Maximum Water-Losing Rate/(kg·m−2·h−1) |
---|---|---|---|---|---|
0.35 | cement paste | 1.0 | 180 | 16.832 | 0.304 |
mortar | 0.403 | 120 | 6.817 | 0.144 | |
concrete | 0.200 | 80 | 2.950 | 0.111 | |
0.38 | cement paste | 1.0 | 172 | 18.268 | 0.338 |
mortar | 0.408 | 104 | 7.289 | 0.178 | |
concrete | 0.203 | 72 | 3.135 | 0.111 | |
0.41 | cement paste | 1.0 | 164 | 19.483 | 0.411 |
mortar | 0.413 | 96 | 7.978 | 0.222 | |
concrete | 0.207 | 68 | 4.204 | 0.154 |
Material | State | Porosity/% | Average Pore Diameter/nm | |||
---|---|---|---|---|---|---|
<100 nm | 100~1000 nm | >1000 nm | Total Porosity | |||
Cement paste | Saturated | 11.98 | 0.51 | 0.48 | 12.97 | 10.9 |
Dry | 18.70 | 0.45 | 0.89 | 20.04. | 18.8 | |
Mortar | Saturated | 4.33 | 2.60 | 3.00 | 9.93 | 17.7 |
Dry | 3.29 | 7.64 | 2.85 | 13.78 | 110 |
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Du, X.; Li, Z.; Tong, T.; Li, B.; Liu, H. Isothermal Drying Process and its Effect on Compressive Strength of Concrete in Multiscale. Appl. Sci. 2019, 9, 4015. https://doi.org/10.3390/app9194015
Du X, Li Z, Tong T, Li B, Liu H. Isothermal Drying Process and its Effect on Compressive Strength of Concrete in Multiscale. Applied Sciences. 2019; 9(19):4015. https://doi.org/10.3390/app9194015
Chicago/Turabian StyleDu, Xiangqin, Zongli Li, Taotao Tong, Bo Li, and Hengjie Liu. 2019. "Isothermal Drying Process and its Effect on Compressive Strength of Concrete in Multiscale" Applied Sciences 9, no. 19: 4015. https://doi.org/10.3390/app9194015
APA StyleDu, X., Li, Z., Tong, T., Li, B., & Liu, H. (2019). Isothermal Drying Process and its Effect on Compressive Strength of Concrete in Multiscale. Applied Sciences, 9(19), 4015. https://doi.org/10.3390/app9194015