Effects of Atmospheric Pressure on Developmental Characteristics and the Stability of Air Entraining Agent for Concrete

Abstract

In order to ascertain the effects of atmospheric pressure on developmental characteristics and the stability of AEA (air-entraining agent) solution bubbles, AEA solution experiments and AEA solution bubble experiments were, respectively, conducted in Peking (50 m, 101.2 kPa) and Lhasa (3,650 m, 63.1 kPa). Surface tensions and inflection-point concentrations were tested based on AEA solutions, whilst developmental characteristics, thicknesses and elastic coefficients of liquid films were tested based on air bubbles of AEA solutions. The study involved three types of AEAs, which were TM-O, 226A, and 226S. The experimental results show that initial sizes of TM-O, 226A, and 226S are, respectively, increased by 43.5%, 17.5%, and 3.8%. With the decrease of ambient pressure, the drainage rate and the drainage index of AEA solution bubbles increase. Interference experiments show that the liquid film thicknesses of all tested AEA solution bubbles are in micron scales. When the atmospheric pressure decreases from 101.2 to 63.1 kPa, the liquid film thicknesses of three types of AEA solutions decrease in various degrees; and film elasticities at critical thicknesses increase. Liquid film of 226S solution bubbles is the most stable, presenting as a minimum thickness variation. It should be noted that elastic coefficient of liquid film only represents the level at critical thickness, thus it can not be applied as the only evaluating indicator of bubble stability. For a type of AEA, factors affecting the stability of its bubbles under low atmospheric pressure include initial bubbles size, liquid film thickness, liquid film elasticity, ambient temperature, etc.

Keywords

air-entraining agent / surface tension / bubble size / liquid film thickness / liquid film elasticity / atmospheric pressure

References

[1] Ge X, Ge Y, Dd YB, et al. Effect of Low Air Pressure on Mechanical Properties and Shrinkage of Concrete[J]. Magazine of Concrete Research, 2018, 70(18): 919-927.

[2] Ge X, Ge Y, Li QF, et al. Effect of Low Air Pressure on the Durability of Concrete[J]. Construction and Building Materials, 2018, 187: 830-838.

[3] Wang SJ, Chen JB, Zhang JZ, et al. Development of Highway Constructing Technology in the Permafrost Region on the Qinghai-Tibet plateau[J]. Science in China(Series E:Technological Sciences), 2009, 52(02): 497-506.

[4] Kosmatka SH, Kerkhoff B, Panarese WC. Design and Control of Concrete Mixtures[M], 2002 Skokie, IL: Portland Cement Association. Vol. 5420

[5] Li Y, Wang ZD, Wang L. The Influence of Atmospheric Pressure on Air Content and Pore Structure of Air-entrained Concrete[J]. Journal of Wuhan University of Technology -Materials Science Edition, 2019, 34(06): 1365-1370.

[6] Li Y, Wang ZD, Xue C, et al. Influence of Low Air Pressure on the Performance of Concrete in Road Engineering[J]. China Journal of Highway and Transport, 2021, 34(09): 194-202.

[7] Li XF, Fu Z, Luo Z. Effect of Atmospheric Pressure on Air Content and Air Void Parameters of Concrete[J]. Magazine of Concrete Research, 2015, 67(7–8): 391-400.

[8] Li XF, Yang P. Effect of Low Atmospheric Pressure on Bubble Stability of Air-entrained Concrete[J]. Advances in Civil Engineering, 2021: 5 533 437

[9] He R, Wang T, Chen HX, et al. Impact of Qinghai-Tibet Plateau’s Climate on Strength and Permeability of Concrete[J]. China Journal of Highway and Transport, 2020, 33(07): 29-41.

[10] Huo J, Wang Z, Chen H, et al. Impacts of Low Atmospheric Pressure on Properties of Cement Concrete in Plateau Areas: A Literature Review[J]. Materials, 2019, 12(9): 1384

[11] Chen X, Liu X, Tian B, et al. Effect of Low Atmospheric Pressure on Air Entrainment in Cement-based Materials: An On-site Experimental Study at Different Elevations[J]. Materials, 2020, 13(18): 3975

[12] Shi Y, Yang HQ, Zhou SH, et al. Effect of Atmospheric Pressure on Performance of AEA and Air Entraining Concrete[J]. Advances in Materials Science and Engineering, 2018: 6528412

[13] Liu X, Chen X, Tian B, et al. Cement Concrete Properties in Low Atmospheric Pressure: A Review[J]. Journal of the Chinese Ceramic Society, 2021, 49(08): 1743-1752.

[14] Li LH, Chen X, Tian B, et al. Effect of Atmospheric Pressure on Air-entraining Performance of Air-entraining Agent of Concrete[J]. Journal of Building Materials, 2021, 24(04): 866-873.

[15] Ley MT, Chancey R, Juenger MCG, et al. The Physical and Chemical Characteristics of the Shell of Air-entrained Bubbles in Cement Paste[J]. Cement and Concrete Research, 2009, 39(5): 417-425.

[16] Zeng XH, Lan XL, Zhu HS, et al. Investigation on Air-voids Structure and Compressive Strength of Concrete at Low Atmospheric Pressure[J]. Cement and Concrete Composites, 2021, 122(7): 104-139.

[17] Afanasyev YD, Andrews GT, Deacon CG. Measuring Soap Bubble Thickness with Color Matching[J]. American Journal of Physics, 2011, 79(10): 1079-1082.

[18] Vannoni M, Sordini A, Gabrieli R, et al. Measuring the Thickness of Soap Bubbles with Phase-shift Interferometry[J]. Optics Express, 2013, 21(17): 19657-19667.

[19] Rosen MJ, Solash J. Factors Affecting Initial foam Height in the Ross-Miles Foam Test[J]. Journal of the American Oil Chemists’ Society, 1969, 46(8): 399-402.

[20] Varadaraj R, Bock J, Valint P, et al. Relationship Between Fundamental Interfacial Properties and Foaming in Linear and Branched Sulfate, Ethoxysulfate, and Ethoxylate Surfactants[J]. Journal of Colloid and Interface Science, 1990, 140(1): 31-34.

[21] Yekeen N, Manan MA, Idris AK, et al. Influence of Surfactant and Electrolyte Concentrations on Surfactant Adsorption and Foaming Characteristics[J]. Journal of Petroleum Science and Engineering, 2017, 149: 612-622.

[22] Majeed T, Sølling TI, Kamal MS. Foamstability: The Interplay Between Salt-, Surfactant-and Critical Micelle Concentration[J]. Journal of Petroleum Science and Engineering, 2020, 187: 106-871.

[23] Ke GJ, Zhang J, Tian B, et al. Characteristic Analysis of Concrete Air Entraining Agents in Different Media[J]. Cement and Concrete Research, 2020, 135: 106142.

[24] Chartier Germain. Introduction to Optics[M], 2005 New York, USA: Springer. 259-298.

[25] Rosen MJ, Kunjappu JT. Surfactants and Interfacial Phenomena(Fourth Edition)[M], 2012 New Jersey, USA: John Wiley & Sons. 50-53.

[26] Martin P, Brochard-Wyart F. Dewetting at Soft Interfaces[J]. Physical Review Letters, 1998, 80(15): 3296-3299.

[27] Pugh RJ. Experimental Techniques for Studying the Structure of Foams and Froths[J]. Advances in Colloid and Interface Science, 2005, 114: 239-251.

[28] Gibbs JW. On the Equilibrium of Heterogeneous Substances[J]. American Journal of Science, 1878, 3(96): 441-458.

[29] Marangoni C. Difesa Della Teoria Dell’elasticità Superficiale Dei Liquidi. Plasticità Superficiale[J]. Il Nuovo Cimento (1869–1876), 1870, 3: 50-68.

[30] Sheludko A. Colloid Chemistry[M], 1966 New York: Elsevier Publ. Co.. 1-2.

[31] Rosen MJ. Correction of the Sheludko Equation for Gibbs Elasticity[J]. Journal of Colloid and Interface Science, 1967, 24(2): 279-280.