PSI - Issue 17

O. Plekhov et al. / Procedia Structural Integrity 17 (2019) 602–609 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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the water-ice phase transition in a porous medium at negative temperatures. To account for this effect, two models were added to the Comsol package with the aim to describe the process of phase transition in a partially and completely saturated porous medium. We solved three boundary problems: the formation of the frozen soil zone near single freeze well, the coalescence of the frozen zones extending from two freezing wells and the growth of a closed frozen cylinder. The analysis of the obtained solutions showed that the phase transition rate could be described well by a standard two phase transition model. The computation of the structure and strength properties of the AGF system, as well as the distribution of mechanical stresses around the generated ice barrier, requires a more complicated model. Analysis of the solution of the problem on the coalescence of two zones of frozen soil showed that the redistribution of moisture content leads to a decrease of humidity in the coalescence zone and, as a consequence, to inhomogeneous content of ice in the ice barrier. In particular, the difference in ice content was by more than 30% at the points near the freeze column and at the points of closure of the frozen zones. The redistribution of moisture content is especially pronounced in partially saturated soil in the inner closed region of the growing ice barrier. The motion of the liquid towards the front of phase transition leads to a drop of humidity within the AGF system by more than 10%. This effect can compensate for the pressure caused by a damage of the soil horizon during the water-ice phase transition and cause the slowing down of the water level in the hydro-observation wells. Numerical simulation of the formation of the AGF system taking into account the real thermo-mechanical parameters of the Petrikov mine (Belorussia) showed that this effect can be responsible for the observable retardation of water yield of the hydroelectric well during the formation of ice barrier around the first shaft of the Petrikov mine (Belorussia). Taber S., 1930. The mechanics of frost heaving. J. Geol. 38, 303-317 Istomin V.A., Chyvilin E.M., Machonona N.A., Buchanov B.A., 2009. Determination of temperature determination of the temperature dependence of the unfrozen water content in soils on the moisture potential. Kriosphera Semli. 2, 35-43 (in Russian) Grigoriev B.V. 2013 Experimental study of freezing of sandy ground in equilibrium and disequilibrium conditions. Nauchno-tekhnicheskie Vedomosti SPbGPU. 2, 216-220 (in Russian) Bronfenbrener L., 2013. Non-equilibrium crystallization in freezing porous media: Numerical solution. Cold region science and technology. 85, 137-149. Panteleev I., Kostina A., Zhelnin M., Plekhov A., Levin L., 2017. Intellectual monitoring of artificial ground freezing in the fluid-saturated rock mass. Procedia Structural Integrity. 5, 492-499 Bittelli, M., Flury, F., Roth, K., 2004. Use of dielectric spectroscopy to estimate ice content in frozenporous media. Water Resour. Res. 40, 1 – 11. Black, P.B., 1995. Rigid Ice Model of Secondary Frost Heave. Cold Regions Research & Engineering Laboratory, US Army Corps of Engineers. Bouyoucos, G.J. 1920. Degree of temperature to which soils can becooled without freezing. Journal of Agricultural Research, 20: 267 – 269 Danielian Yu.S., Yanitcky P.A., Cheverev V.G., Lebedenko Yu.P., 1983. Experimental and theoretical heat and mass transfer research in frozen soils. J. Eng. Geol. 3, 77 – 83. Ershov, E.D., 1979. Phase composition in the frozen rocks. Nauka, Moscow. 240 pp. Ershov, E.D., Williams, P.J. (Eds.), 2004. General Geocryology (Studies in Polar Research). Cambridge University Press. 604 pp. Feldman, G.M., 1988. Moisture movement inmelted and frozen soils. Nauka, Novosibirsk. 258 pp. Fisher, R.A. 1924. The freezing of water in capillary systems: A critical discussion. Journal of Physical Chemistry, 28: 36 – 67 Grechischev, S.E., Chistotinov, L.E., Shur Yu, L., 1980. Cryogenic physic-geological processes and their prediction. Nedra, Moscow. 324 pp. Harlan, R.L. 1973. Analysis of coupled heat-fluid transport in partially frozen soil. Water Resource Research. 9, 1314 – 1323. Konrad, J.M., 2005. Estimation of the segregation potential of fine-grained soils using the frost heave response of two reference soils. Can. Geotech. J. 42, 38 – 50. Michalowski, R.L., Zhu, M., 2006. Frost heave modeling using porosity rate function. . Numer. Anal. Meth. Geomech. 30, 703 – 722. Nakano, Y., 1992. Mathematical model on the steady growth of an ice layer in freezing soils. In: Maeno, N., Mondoh, T. (Eds.), Physics and Chemistry of ice. Hokkaido University Press, pp. 364 – 369. Schofield, R.K. 1935. The PF of the water in soil. Transactions, 3rd International Congress of Soil Science, Vol. 2, pp. 37 – 48 Taylor, G.S., Luthin, J.N., 1978. A model for coupled heat and moisture transfer during soil freezing. Can. Geotech. J. 15 (4), 548 – 555. Panteleev, I. A., Kostina, A. A., Plekhov, O. A., Levin L.Yu., 2017. Numerical simulation of artificial ground freezing in a fluid-saturated rock mass with account for filtration and mechanical processes. Sciences in cold and arid regions. V. 9.,N. 4. pp. 363-377. Acknowledgements This research was supported by 19-77-30008 project (Russian Science Foundation). References