Model of grout filtration in a porous soil

21st International Scientific Conference on Advanced in Civil Engineering "Construction - The Formation of Living Environment"

土木建筑工程

Gorbunova, Tatiana^1,2

Moscow State University of Civil Engineering, Yaroslavskoe shosse 26, Moscow

129337, Russia^1

Moscow Polytechnic University, Bolshaya Semenovskaya str. 38, Moscow

107023, Russia^2

关键词: Discontinuous solutions;    Filtration coefficient;    Filtration in a porous soil;    First order differential equation;    Initial and boundary conditions;    Mathematical equations;    Particles concentration;    Suspended particulates;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/365/4/042007/pdf
DOI  :  10.1088/1757-899X/365/4/042007

学科分类：土木及结构工程学

来源: IOP

【 摘 要 】

To strengthen the foundations and protect them from ground water, liquid grout is pumped under pressure into a loose porous soil. Modern construction techniques use colloids or suspensions which form a waterproof layer upon solidification. Calculation of grout distribution in a porous soil is an important part of designing buildings and structures. The distribution of suspended particulates in unconsolidated soil is described by mathematical equations of particles filtration in the porous media. The aim of this work is modelling of suspended particles transport and deposit formation in a porous soil for different filtration modes. The distributions of solid particles of different sizes transported by the carrier fluid and retained on the frame of the porous medium at different kinetic rates of deposit growth are examined. Model of one-dimensional filtration with size-exclusion particle retention mechanism includes a hyperbolic system of the first order differential equations with inconsistent initial and boundary conditions that leads to discontinuous solutions. A modified mathematical model for polydisperse media with the competition between particles of different sizes for small pores is considered. The computational scheme for numerical solutions is constructed by finite difference method. Optimization methods to improve convergence and reduce computation time are used. A multi-particle model of grout filtration in a porous soil is constructed, considering the variety of sizes of suspended particles. A numerical calculation of the problem is performed for various blocking filtration coefficient. Solutions are obtained with a discontinuity on the concentration front. Approbation of the obtained numerical solutions is carried out. Plots of the suspended and retained particles concentrations depending on time and coordinates are constructed. A new model of multi-particle transport in a porous medium widely extends the design capabilities of waterproof underground walls. The solution of the filtration problem for solid particles of different sizes makes it possible to calculate the optimal composition of grout for constructing a waterproof layer in a porous soil. The developed computing finite-difference methods allow to obtain the numerical solution of complex systems of equations with good accuracy and a moderate amount of computation.