Title:
Simulation Analysis of Pumping and Its Variability for Manufactured Sand Concrete
Author(s):
Guoju Ke, Jiaqian Wang, and Bo Tian
Publication:
Materials Journal
Volume:
116
Issue:
3
Appears on pages(s):
35-42
Keywords:
air void structure; megabyte (MB) value; pumpability; pumping variability; stone dust (SD) content; superabsorbent polymer (SAP)
DOI:
10.14359/51714504
Date:
5/1/2019
Abstract:
To solve the problem of manufactured sand concrete in the pumping process being very prone to plugging, a pumping resistance tester is used to test the influences of stone dust (SD) content and megabyte (MB) value of the manufactured sand, fly ash, silica fume, superabsorbent polymer (SAP), and air-entraining agent on the pumpability of manufactured sand concrete with different intensities, including push distance and pumping resistance. Furthermore, variations in the performance of the manufactured sand concrete before and after pumping are analyzed, including slump, slump flow, density, push distance, pumping resistance, compressive strength, chloride ion anti-permeability, and air void structure. Results show that SAP has shown a significant reduction in pumping resistance, both in low-strength concrete and in high-strength concrete. In the process of pumping, the pumping pressure causes the air void structure of the hardened manufactured sand concrete to change. The number of big air voids decreases, air void ratio increases, total porosity is reduced, and the resistance to chloride ion permeability is superior to the level before pumping.
Related References:
1. Hover, K. C., and Phares, R. J., “Impact of Concrete Placing Method on Air Content, Air-Void System Parameters, and Freeze-Thaw Durability,” Transportation Research Record: Journal of the Transportation Research Board, V. 1532, No. 1, 1996, pp. 1-8. doi: 10.1177/0361198196153200101
2. Lessard, M.; Baalbaki, M.; and Aïtcin, P.-C., “Effect of Pumping on Air Characteristics of Conventional Concrete,” Transportation Research Record: Journal of the Transportation Research Board, V. 1532, No. 1, 1996, pp. 9-14. doi: 10.1177/0361198196153200102
3. Ke, G. J.; Tian, B.; and Wang, J. L., “Effects of Air-Entraining Agents and Welan Gum on Rheological Properties of Fresh Cement Mortar,” The 14th International Congress on the Chemistry of Cement, Beijing, China, 2015.
4. Le, H. D.; Kadri, E. H.; Aggoun, S.; Vierendeels, J.; Troch, P.; and De Schutter, G., “Effect of Lubrication Layer on Velocity Profile of Concrete in a Pumping Pipe,” Materials and Structures, V. 48, No. 12, 2015, pp. 1-13. doi: 10.1617/s11527-014-0458-5
5. Choi, M.; Roussel, N.; Kim, Y.; and Kim, J., “Lubrication Layer Properties during Concrete Pumping,” Cement and Concrete Research, V. 45, No. 1, 2013, pp. 69-78. doi: 10.1016/j.cemconres.2012.11.001
6. Choi, M. S.; Kim, Y. J.; and Kwon, S. H., “Prediction on Pipe Flow of Pumped Concrete Based on Shear-Induced Particle Migration,” Cement and Concrete Research, V. 52, No. 10, 2013, pp. 216-224. doi: 10.1016/j.cemconres.2013.07.004
7. Feys, D.; Khayat, K. H.; and Khatib, R., “How Do Concrete Rheology, Tribology, Flow Rate and Pipe Radius Influence Pumping Pressure?” Cement and Concrete Composites, V. 66, 2015, pp. 38-46. doi: 10.1016/j.cemconcomp.2015.11.002
8. Perrot, A.; Lecompte, T.; Khelifi, H.; Brumaud, C.; Hot, J.; and Roussel, N., “Yield Stress and Bleeding of Fresh Cement Pastes,” Cement and Concrete Research, V. 42, No. 7, 2012, pp. 937-944. doi: 10.1016/j.cemconres.2012.03.015
9. Luo, B.; Liu, W.; and Lin, W., “Comparative Experimental Study on the Performance of Concrete Pumps before and after Delivery,” Concrete (London), No. 4, 2015, pp. 123-126. (in Chinese)
10. Li, B.; Ke, G.; and Zhou, M., “Influence of Manufactured Sand Characteristics on Strength and Abrasion Resistance of Pavement Cement Concrete,” Construction and Building Materials, V. 25, No. 10, 2011, pp. 3849-3853. doi: 10.1016/j.conbuildmat.2011.04.004
11. ASTM C143/C143M-03, “Standard Test Method for Slump of Hydraulic Cement Concrete,” ASTM International, West Conshohocken, PA, 2003, 4 pp.
12. ASTM C138/C138M-01a, “Standard Test Method for Density (Unit Weight), Yield, and Air Content (Gravimetric) of Concrete,” ASTM International, West Conshohocken, PA, 2001, 4 pp.
13. GB/T 50081-2002, “Standard Test Method for Mechanical Properties of Ordinary Concrete,” China Building Industry Press, Beijing, China, 2003, 4 pp.
14. JSCE F509, “Test Method for Deformability of Fresh Concrete Using a Pumping Tester,” Japan Materials Society, 2010.
15. ASTM C457/C457M-11, “Standard Test Method for Microscopical Determination of Parameters of the Air-Void System in Hardened Concrete,” ASTM International, West Conshohocken, PA, 2016, 18 pp.
16. Li, B.-X.; Wang, D.-L.; He, G.-J.; and Zhou, M.-K., “Study on Effect of Methylene Blue Value of Manufactured Sand on Performance of Concrete,” Water Resources and Hydropower Engineering, V. 40, No. 4, 2009, pp. 30-36. (in Chinese)
17. Tang, L., and Nilsson, L. O., “Rapid Determination of the Chloride Diffusivity in Concrete by Applying an Electrical Field,” ACI Materials Journal, V. 89, No. 1, Jan.-Feb. 1992, pp. 49-53.
18. NT BUILD 492, “Concrete, Mortar and Cement-Based Repair Materials: Chloride Migration Coefficient from Non-Steady-State Migration Experiments,” NORDTEST, Espoo, Finland, 1999, pp. 1-8.