Tokarev M. Quality improvement of porous composite materials by saturation of hardened liquids

The thesis aims to develop a technology of composite materials converting to provide them with heightened strength, density, water resistance and durability by filling of the porous space of matrix with percolating mixture which becomes hard in the matrix pores; to develop and substantiate physical and mathematical model of the process of filling of the porous space of percolated body. Methods of improving strength of cement concrete based on percolation of hardened concrete with liquid mixtures which become hard in the concrete body are examined. A critical analysis of technology of concrete strengthening by percolation is made and the ways of improving its effectiveness are defined. Methods of percolating porous bodies with liquid are examined. A physical model of the percolation process is developed and on its basis the analysis of effectiveness of existing methods is made. Concrete components are analyzed on three levels: macrostructure, mezostructure and microstructure. The porosity role is defined and the possibility of its use for percolating more viscous liquids is presented. The analysis of porous materials percolation methods on the basis of physical models is made. A possibility of moisture saturation by using doubled system: vacuum is in pores-excessive pressure is in surrounding liquid is defined. Processes of physical and chemical interaction of substances which are included in composition of composite materials are studied. The theoretical analysis is conducted and an intensive method of percolation is developed. Experimental data are obtained. Two-stage percolation mode is developed: creation and maintenance of vacuum inside a product and further pores percolation with hardening liquids.